17-High Availability Command Reference

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10-BFD commands
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10-BFD commands 407.27 KB

BFD commands

bfd authentication-mode

Use bfd authentication-mode to configure the BFD authentication mode for single-hop BFD control packets.

Use undo bfd authentication-mode to restore the default.

Syntax

bfd authentication-mode { hmac-md5 | hmac-mmd5 | hmac-msha1 | hmac-sha1 | m-md5 | m-sha1 | md5 | sha1 | simple } key-id { cipher | plain } string

undo bfd authentication-mode

Default

Single-hop BFD control packets are not authenticated.

Views

Interface view

BFD template view

Static BFD session view

Predefined user roles

network-admin

Parameters

hmac-md5: Specifies the HMAC MD5 algorithm.

hmac-mmd5: Specifies the HMAC Meticulous MD5 algorithm.

hmac-msha1: Specifies the HMAC Meticulous SHA1 algorithm.

hmac-sha1: Specifies the HMAC SHA1 algorithm.

m-md5: Specifies the Meticulous MD5 algorithm.

m-sha1: Specifies the Meticulous SHA1 algorithm.

md5: Specifies the MD5 algorithm.

sha1: Specifies the SHA1 algorithm.

simple: Specifies the simple authentication mode.

key-id: Sets the authentication key ID in the range of 1 to 255.

cipher: Specifies a key in encrypted form.

plain: Specifies a key in plaintext form. For security purposes, the key specified in plaintext form will be stored in encrypted form.

string: Specifies the key. Its plaintext form is a case-sensitive string of 1 to 16 characters. Its encrypted form is a case-sensitive string of 33 to 53 characters.

Usage guidelines

Use this command to enhance BFD session security.

BFD version 0 does not support this command. The configuration does not take effect.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for single-hop detection.

Examples

# Configure HundredGigE 1/0/1 to perform simple authentication for single-hop BFD control packets, setting the authentication key ID to 1 and plaintext key to 123456.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd authentication-mode simple 1 plain 123456

bfd container reserve local-discriminator

Use bfd container reserve local-discriminator to configure BFD session local discriminators reserved for third-party containers.

Use undo bfd container reserve local-discriminator to cancel reservation of BFD session local discriminators for third-party containers.

 

 

NOTE:

This command is supported only in R5212P01 and later versions.

 

Syntax

bfd container reserve local-discriminator discr-value1 [ to discr-value2 ]

undo bfd container reserve local-discriminator

Default

No BFD session local discriminators are reserved for third-party containers.

Views

System view

Predefined user roles

network-admin

Parameters

discr-value1: Specifies a local discriminator reserved for third-party containers, in the range of 1048576 to 4026531840.

discr-value1 to discr-value2: Specifies a local discriminator range reserved for third-party containers. The value range for both the discr-value1 and discr-value2 arguments is 1048576 to 4026531840. The value for the discr-value2 argument must be greater than or equal to the value for the discr-value1 argument.

Usage guidelines

Application scenarios

Comware 9 supports deploying Guest Shell containers, Docker containers, Comware-based RPM applications, Guest Shell container-based applications, and Docker container-based applications on H3C physical devices. When BFD operates in third-party containers deployed on H3C physical devices, BFD packets might be dropped. Use this command to solve the issue. For more information about containers, see common container and open application configuration in Application Hosting Configuration Guide.

Operating mechanism

For BFD to operate in a third-party container deployed on an H3C physical device, the container must receive and transmit BFD packets. When the destination IP address of BFD packets is the IP address of the H3C physical device, these packets are managed by Comware and cannot be sent to the container.

After you execute this command, the H3C physical device reserves BFD session local discriminators for the container. When the Your Discriminator field value in a BFD packet received by the H3C physical device is a reserved BFD session discriminator, Comware does not process the packet. Instead, Comware delivers the packet to the kernel, which then forwards the packet to the third-party container.

Restrictions and guidelines

If you execute this command multiple times, the most recent configuration takes effect.

This command cannot resolve the issue that a BFD session between two containers cannot come up.

After you configure the bfd container reserved local-discriminator command on the device, the SRv6 BFD feature cannot operate correctly and stays in inactive state.

This command is typically reserved for third-party containers. BFD does not process the packets associated with this command.

If the discriminator negotiated by the container is not within the range of 1048576 to 4026531840, you must delete the session on the container and re-create it until the discriminator negotiated by the container is within the range of 1048576 to 4026531840.

Examples

# Reserve BFD session local discriminators 1048576 to 4026531840 for third-party containers.

<Sysname> system-view

[Sysname] bfd container reserve local-discriminator 1048576 to 4026531840

bfd dampening

Use bfd dampening to configure BFD session flapping suppression.

Use undo bfd dampening to disable BFD session flapping suppression.

Syntax

bfd dampening [ maximum maximum-interval initial initial-interval secondary secondary-interval ]

undo bfd dampening

Default

BFD sessions are not suppressed.

Views

System view

Predefined user roles

network-admin

Parameters

maximum-interval: Specifies the maximum time a BFD session is suppressed, in the range of 1 to 3600 seconds. The default is 20 seconds.

initial-interval: Specifies the amount of time a BFD session is suppressed for the first time. The value range for the initial-interval argument is 1 to 3600 seconds. The default is 6 seconds.

secondary-interval: Specifies the amount of time a BFD session is suppressed for the second time. The value range for the secondary-interval argument is 1 to 3600 seconds. The default is 10 seconds.

Usage guidelines

When BFD detects a link failure, it tears down the BFD session and notifies the upper-layer protocol of the failure. When the upper-layer protocol re-establishes a neighbor relationship, the BFD session comes up again. BFD session flaps occur when a link fails and recovers repeatedly, which consumes significant system resources and causes network instability.

This command allows you to suppress BFD session flapping by using the initial-interval, secondary-interval, and maximum-interval arguments.

·     A BFD session is suppressed within the specified interval. The suppression time does not exceed the maximum-interval.

·     After a BFD session goes down for the second time, it cannot be re-established within the initial-interval.

·     After a BFD session goes down for the third time, it cannot be re-established within the secondary-interval.

·     After a BFD session goes down for the fourth time and at any later time, the following rules apply:

¡     If secondary-interval × 2n-3 is smaller than or equal to the maximum-interval, the BFD session cannot be re-established within the secondary-interval × 2n-3.

¡     If secondary-interval × 2n-3 is greater than the maximum-interval, the BFD session cannot be re-established within the maximum-interval.

The letter n, starting from 4, is the number of times the BFD session flaps.

Examples

# Enable BFD session flapping suppression, and set the maximum-interval, initial-interval, and secondary-interval to 12 seconds, 4 seconds, and 8 seconds, respectively.

<Sysname> system-view

[Sysname] bfd dampening maximum 12 initial 4 secondary 8

bfd demand enable

Use bfd demand enable to enable the Demand BFD session mode.

Use undo bfd demand enable to restore the default.

Syntax

bfd demand enable

undo bfd demand enable

Default

The BFD session is in Asynchronous mode.

Views

Interface view

Predefined user roles

network-admin

Usage guidelines

In Demand mode, the device periodically sends BFD control packets. If the peer end is operating in Asynchronous mode (default), the peer end stops sending BFD control packets. If the peer end is operating in Demand mode, both ends stop sending BFD control packets. When a system in Demand mode wants to verify the connectivity to another system, it sends several BFD control packets with the Poll (P) bit set at the negotiated transmit interval. If no response is received within the detection interval, the session is considered down. If the connectivity is found to be up, no more BFD control packets are sent until the next command is issued. As a best practice, configure the bfd echo enable command together with this command to detect connectivity by sending Echo packets. If the device does not receive any Echo packets from the peer end, it considers the session down.

In Asynchronous mode, the device periodically sends BFD control packets. The device considers that the session is down if it does not receive any BFD control packets within a specific interval.

BFD version 0 does not support this command. The configuration does not take effect.

Examples

# Enable the Demand BFD session mode on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd demand enable

Related commands

bfd echo enable

bfd detect-interface

Use bfd detect-interface source-ip to associate the interface state with BFD.

Use undo bfd detect-interface to remove the association between the interface state and BFD.

Syntax

bfd detect-interface source-ip ip-address [ discriminator local local-value remote remote-value ] [ template template-name ]

undo bfd detect-interface

Default

The interface state is not associated with BFD.

Views

Interface view

Predefined user roles

network-admin

Parameters

ip-address: Specifies the source IP address for BFD control packets.

discriminator: Specifies BFD session discriminators. If you do not specify discriminators, the device obtains BFD session discriminators through autonegotiation.

local local-value: Specifies the local discriminator. The value range for the local-value argument is 6001 to 8000.

remote remote-value: Specifies the remote discriminator in the range of 1 to 4294967295.

template template-name: Specifies a template by its name, a case-sensitive string of 1 to 63 characters. If you specify a nonexistent template or do not specify a template, the BFD session uses the BFD parameters configured in interface view. If you first specify a nonexistent template and then create the template, the BFD session uses the parameters configured in the template.

Usage guidelines

By creating a BFD session for single-hop detection through exchange of BFD control packets, this feature implements fast link detection.. When BFD detects a link fault, it sets the link layer protocol state to DOWN(BFD). This behavior helps applications relying on the link layer protocol state achieve fast convergence. The source IP address of control packets is specified manually, and the destination IP address is fixed at 224.0.0.184. As a best practice, specify the IP address of the interface as the source IP address. If the interface does not have an IP address, specify a unicast IP address other than 0.0.0.0 as the source IP address.

You can only associate the state of a Layer 3 Ethernet interface with BFD.

This command must be configured on both ends of the link for a BFD session to be established.

If the peer device does not support obtaining BFD session discriminators through autonegotiation, you must specify the discriminators on both the local and peer devices. Without the discriminators, the BFD session cannot come up.

The BFD session discriminators must match on the local and peer devices. For example, if you configure bfd detect-interface source-ip 20.1.1.1 discriminator local 6002 remote 6020 on the local device, you must configure bfd detect-interface source-ip 20.1.1.1 discriminator local 6020 remote 6002 on the peer device.

The local discriminators of BFD sessions for interfaces on the same device must be different.

The echo function does not take effect on BFD sessions associated with interface states.

To detect data link layer connectivity for an interface, execute one of the following commands:

·     bfd detect-interface source-ip

·     bfd static session-name peer-ip default-ip interface interface-type interface-number source-ip ip-address

Examples

# Associate HundredGigE 1/0/1 with BFD to detect the interface state, and specify the source IP address for BFD control packets as 20.1.1.1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd detect-interface source-ip 20.1.1.1

Related commands

link-protocol (Interface Command Reference)

bfd static

bfd detect-interface first-fail-timer

Use bfd detect-interface first-fail-timer to configure the timer that delays reporting the first BFD session establishment failure to the data link layer.

Use undo bfd detect-interface first-fail-timer to restore the default.

Syntax

bfd detect-interface first-fail-timer seconds

undo bfd detect-interface first-fail-timer

 

Default

The first BFD session establishment failure is not reported to the data link layer.

Views

Interface view

Predefined user roles

network-admin

Parameters

seconds: Specifies the timeout time that reports the first BFD session establishment failure to the data link layer. The value range for this argument is 1 to 10000 seconds.

Usage guidelines

If the BFD session fails to be established when the timer expires, BFD reports the failure to the data link layer and sets the data link layer state of the interface to DOWN(BFD). This behavior rapidly identifies the interfaces for which BFD sessions fail to be established. In this case, the BFD session state is displayed as Down in the display bfd session command output. The line protocol state of the interface is displayed as DOWN(BFD) in the display interface command output.

If you execute the bfd detect-interface source-ip command on the local end, the BFD session for detecting the local interface state fails to be established when the following conditions exist:

·     The bfd detect-interface source-ip command is not executed on the remote end.

·     The local and remote ends have mismatching BFD authentication settings.

Examples

# Configure the timer that delays reporting the first BFD session establishment failure as 10 seconds for HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd detect-interface first-fail-timer 10

Related commands

bfd detect-interface source-ip

display interface (Interface Command Reference)

bfd detect-interface special-processing

Use bfd detect-interface special-processing to enable special processing for BFD sessions.

Use undo bfd detect-interface special-processing to disable special processing for BFD sessions.

Syntax

bfd detect-interface special-processing [ admin-down | authentication-change | session-up ] *

undo bfd detect-interface special-processing [ admin-down | authentication-change | session-up ] *

Default

All types of special processing for BFD sessions are disabled.

Views

Interface view

Predefined user roles

network-admin

Parameters

admin-down: Notifies a session down event to the data link layer upon receipt of a BFD packet with the State field as AdminDown. This keyword helps rapidly discover interfaces on which BFD sessions are manually shut down. If you do not specify this keyword, the device sets the BFD session state to Down, but does not notify the session down event to the data link layer.

authentication-change: Immediately sets the session to down state upon a local authentication information change. This keyword helps rapidly discover interfaces with authentication information changes. If you do not specify this keyword, the device sets the session to down state if authentication information inconsistency still persists after a period of time.

session-up: Ignores authentication information inconsistency when the local session is up. If a large number of BFD sessions exist, examining authentication information consistency affects device performance. If you do not specify this keyword, the device examines authentication information in incoming BFD packets when the local session state is up. If the authentication information does not match on the two ends, the BFD session is declared down.

Usage guidelines

If you do not specify any parameters, this command enables or disables all types of special processing.

Examples

# Enable all types of special processing for BFD sessions on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd detect-interface special-processing admin-down authentication-change session-up

bfd detect-multiplier

Use bfd detect-multiplier to set the single-hop detection time multiplier for control packet mode and echo packet mode.

Use undo bfd detect-multiplier to restore the default.

Syntax

bfd detect-multiplier value

undo bfd detect-multiplier

Default

The single-hop detection time multiplier is 5 for control packet mode and echo packet mode.

Views

Interface view

BFD template view

Static BFD session view

Predefined user roles

network-admin

Parameters

value: Specifies a detection time multiplier. The value range for this argument is 3 to 50.

Usage guidelines

The detection time multiplier determines the maximum number of concurrent BFD packets (including control packets and echo packets) that can be discarded.

Table 1 Actual detection interval calculation method

Mode

Actual detection interval of the sender

Echo packet mode

Detection time multiplier of the sender × actual packet sending interval of the sender

Control packet mode BFD session in asynchronous mode

Detection time multiplier of the receiver × MAX (minimum receiving interval supported by the sender, minimum sending interval supported by the receiver)

Control packet mode BFD session in demand mode

Detection time multiplier of the sender × MAX (minimum sending interval supported by the sender, minimum receiving interval supported by the receiver)

 

Only the following static BFD sessions support this command:

·     Static BFD sessions in IPv4 control packet mode used for single-hop detection.

·     Static BFD sessions in IPv4 echo packet mode used for single-hop detection.

·     Static BFD sessions in IPv6 control packet mode used for single-hop detection.

·     Static BFD sessions in IPv6 echo packet mode used for single-hop detection.

 Examples

# Set the single-hop detection time multiplier for control packet mode and echo packet mode to 6 on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd detect-multiplier 6

bfd dynamic-udp-port enable

Use bfd dynamic-udp-port enable to enable dynamic modification for the port number of BFD packets.

Use undo bfd dynamic-udp-port enable to disable dynamic modification for the port number of BFD packets.

Syntax

bfd dynamic-udp-port enable

undo bfd dynamic-udp-port enable

Default

Dynamic modification for the port number of BFD packets is disabled.

Views

System view

Predefined user roles

network-admin

mdc-admin

Usage guidelines

Application scenarios

When you use BFD to detect link connectivity between two devices that have multiple available paths (for example, ECMP or aggregate links) between them, the device selects the path for forwarding BFD packets based on the UDP port number. By default, for a specific BFD session, the source port number of BFD packets is randomly generated upon session startup and then keeps unchanged. The destination port number is determined based on the session type, and keeps unchanged during the session.

As a result, the device always uses the same path to forward BFD packets. When the path fails, the BFD session goes down. The network redundancy capabilities are not fully utilized, which might affect the accuracy of link connectivity detection and stability of the network. You can use this feature to resolve the previous issues.

Operating mechanism

When you use BFD to detect link connectivity between two devices, configure the command based on the session mode as follows:

·     For a BFD session in control packet mode, configure this command on both devices.

·     For a BFD session in echo packet mode, configure this command on only the device that sends echo packets.

This command enables the device to modify the port number of BFD packets. The device can then select different paths to forward BFD packets, avoiding the BFD session down issue upon a single link failure. The device modifies the port number as follows:

·     For BFD packets, the device modifies the source port number of the packets.

·     For SBFD packets, the initiator modifies the source port number of the packets, and the reflector modifies the destination port number of the packets.

Restrictions and guidelines

This feature is a proprietary implementation by H3C. As a best practice, do not use this feature in the scenarios where H3C devices collaborate with devices from other vendors. If you do so, BFD session flapping might occur.

This command takes effect only on hardware BFD sessions. This command takes effect on both existing BFD sessions and newly created BFD sessions.

This command takes effect on both BFD and SBFD packets.

Examples

# Enable dynamic modification for the port number of BFD packets.

<Sysname> system-view

[Sysname] bfd dynamic-udp-port enable

bfd echo enable

Use bfd echo enable to enable the echo function.

Use undo bfd echo enable to disable the echo function.

Syntax

bfd echo [ receive | send ] enable

undo bfd echo [ receive | send ] enable

Default

The echo function is disabled.

Views

Interface view

Static BFD session view

Predefined user roles

network-admin

Parameters

receive: Specifies the echo packet receiving capability.

send: Specifies the echo packet sending capability.

Usage guidelines

If you enable the echo function for a BFD session in which control packets are sent and the session comes up, BFD performs the following operations:

·     Periodically sends echo packets to detect link connectivity.

·     Decreases the control packet receiving rate at the same time.

To enable only the echo packet receiving capability, use the bfd echo receive enable command.

To enable only the echo packet sending capability, use the bfd echo send enable command.

If you do not specify the receive or send keyword, the command enables both the echo packet receiving and sending capabilities.

The echo function does not take effect on BFD sessions associated with interface states.

The echo function does not take effect on BFD sessions in control packet mode that use IPv6 link-local addresses.

If you configure both the bfd detect-interface and bfd echo enable commands for an interface, only the bfd detect-interface command takes effect.

BFD version 0 does not support this command. The configuration does not take effect.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for single-hop detection.

Examples

# Enable the echo function on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd echo enable

bfd echo-source-ip

Use bfd echo-source-ip to configure the source IP address of BFD echo packets.

Use undo bfd echo-source-ip to remove the configured source IP address of BFD echo packets.

Syntax

bfd echo-source-ip ip-address

undo bfd echo-source-ip

Default

No source IP address is configured for BFD echo packets.

Views

System view

Predefined user roles

network-admin

Parameters

ip-address: Specifies the source IP address of BFD echo packets. The source IP address must be a valid unicast IPv4 address in dotted decimal notation.

Usage guidelines

As a best practice, execute this command only one end, and do not configure the source IP address to be on the same network segment as any local interface's IP address. If you configure such a source IP address, a large number of ICMP redirect packets might be sent from the peer, resulting in link congestion.

Examples

# Configure the source IP address of BFD echo packets as 8.8.8.8.

<Sysname> system-view

[Sysname] bfd echo-source-ip 8.8.8.8

bfd echo-source-ipv6

Use bfd echo-source-ipv6 to configure the source IPv6 address of BFD echo packets.

Use undo bfd echo-source-ipv6 to remove the configured source IPv6 address of BFD echo packets.

Syntax

bfd echo-source-ipv6 ipv6-address

undo bfd echo-source-ipv6

Default

No source IPv6 address is configured for BFD echo packets.

Views

System view

Predefined user roles

network-admin

Parameters

ipv6-address: Specifies the source IPv6 address for BFD echo packets.

Usage guidelines

The source IPv6 address of echo packets can only be a global unicast address.

As a best practice, execute this command only one end. The source IPv6 address cannot be on the same network segment as any local interface's IP address. Otherwise, a large number of ICMP redirect packets might be sent from the peer, resulting in link congestion.

Examples

# Configure the source IPv6 address of BFD echo packets as 80::2.

<Sysname> system-view

[Sysname] bfd echo-source-ipv6 80::2

bfd init-fail-timer

Use bfd init-fail-timer to set the delay timer for BFD to notify upper-layer protocols of session establishment failures.

Use undo bfd init-fail-timer to restore the default.

Syntax

bfd init-fail-timer seconds

undo bfd init-fail-timer

Default

BFD does not notify upper-layer protocols of session establishment failures.

Views

System view

Predefined user roles

network-admin

Parameters

seconds: Specifies the delay time in the range of 5 to 600 seconds. After the delay time, BFD notifies the upper-layer protocol of session establishment failures.

Usage guidelines

CAUTION

CAUTION:

For session establishment failures caused by configuration mismatches at the two ends, this command can cause the upper-layer protocol to act incorrectly. Therefore, use this command with caution. BFD status mismatch and BFD authentication configuration mismatch are examples of configuration mismatches.

 

This command takes effect only for control packet mode.

In some cases, for an upper-layer protocol to act correctly, BFD must notify the upper-layer protocol of session establishment failures. For example, with this command configured, the link aggregation module can promptly set the state of a member port from Selected to Unselected in the case of a link failure.

Examples

# Set the delay timer to 10 seconds for BFD to notify upper-layer protocols of session establishment failures.

<Sysname> system-view

[Sysname] bfd init-fail-timer 10

bfd min-echo-receive-interval

Use bfd min-echo-receive-interval to set the minimum interval for receiving BFD echo packets.

Use undo bfd min-echo-receive-interval to restore the default.

Syntax

bfd min-echo-receive-interval interval

undo bfd min-echo-receive-interval

Default

The minimum interval for receiving BFD echo packets is 400 milliseconds.

Views

Interface view

BFD template view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for receiving BFD echo packets, in milliseconds. The value takes 0 or is in the range of 3 to 10000.

Usage guidelines

This command sets the BFD echo packet receiving interval, which is the actual BFD echo packet sending interval.

The local end stops sending echo packets after autonegotiation with the remote end if the following conditions are met:

·     The echo mode is enabled on the local end.

·     The minimum interval for receiving BFD echo packets is set to 0 milliseconds on the remote end.

Only the following static BFD sessions support this command:

·     Static BFD sessions in IPv4 control packet mode used for single-hop detection.

·     Static BFD sessions in IPv4 echo packet mode used for single-hop detection.

·     Static BFD sessions in IPv6 control packet mode used for single-hop detection.

·     Static BFD sessions in IPv6 echo packet mode used for single-hop detection.

Examples

# Set the minimum interval for receiving BFD echo packets to 500 milliseconds on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd min-echo-receive-interval 500

bfd min-receive-interval

Use bfd min-receive-interval to set the minimum interval for receiving single-hop BFD control packets.

Use undo bfd min-receive-interval to restore the default.

Syntax

bfd min-receive-interval interval

undo bfd min-receive-interval

Default

The minimum interval for receiving single-hop BFD control packets is 400 milliseconds.

Views

Interface view

BFD template view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for receiving single-hop BFD control packets, in milliseconds. The value range for this argument is 3 to 10000.

Usage guidelines

Use this command to prevent the control packet sending rate of the peer end from exceeding the control packet receiving rate of the local end.

The actual control packet sending interval of the peer end takes the greater value between the following values:

·     Minimum interval for transmitting BFD control packets on the peer end.

·     Minimum interval for receiving BFD control packets on the local end.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for single-hop detection.

Examples

# Set the minimum interval for receiving single-hop BFD control packets to 500 milliseconds on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd min-receive-interval 500

bfd min-transmit-interval

Use bfd min-transmit-interval to set the minimum interval for transmitting single-hop BFD control packets.

Use undo bfd min-transmit-interval to restore the default.

Syntax

bfd min-transmit-interval interval

undo bfd min-transmit-interval

Default

The minimum interval for transmitting single-hop BFD control packets is 400 milliseconds.

Views

Interface view

BFD template view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for transmitting single-hop BFD control packets, in milliseconds. The value range for this argument is 10 to 10000.

Usage guidelines

Use this command to prevent the BFD packet sending rate from exceeding the device capability.

The actual BFD control packet transmitting interval on the local end is the greater value between the following values:

·     Minimum interval for transmitting BFD control packets on the local end.

·     Minimum interval for receiving BFD control packets on the peer end.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for single-hop detection.

Examples

# Set the minimum interval for transmitting single-hop BFD control packets to 500 milliseconds on HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] interface hundredgige 1/0/1

[Sysname-HundredGigE1/0/1] bfd min-transmit-interval 500

bfd multi-hop authentication-mode

Use bfd multi-hop authentication-mode to configure the authentication mode for multihop BFD control packets.

Use undo bfd multi-hop authentication-mode to restore the default.

Syntax

bfd multi-hop authentication-mode { hmac-md5 | hmac-mmd5 | hmac-msha1 | hmac-sha1 | m-md5 | m-sha1 | md5 | sha1 | simple } key-id { cipher | plain } string

undo bfd multi-hop authentication-mode

Default

No authentication is performed.

Views

System view

Static BFD session view

Predefined user roles

network-admin

Parameters

hmac-md5: Specifies the HMAC MD5 algorithm.

hmac-mmd5: Specifies the HMAC Meticulous MD5 algorithm.

hmac-msha1: Specifies the HMAC Meticulous SHA1 algorithm.

hmac-sha1: Specifies the HMAC SHA1 algorithm.

m-md5: Specifies the Meticulous MD5 algorithm.

m-sha1: Specifies the Meticulous SHA1 algorithm.

md5: Specifies the MD5 algorithm.

sha1: Specifies the SHA1 algorithm.

simple: Specifies the simple authentication mode.

key-id: Sets the authentication key ID in the range of 1 to 255.

cipher: Specifies a key in encrypted form.

plain: Specifies a key in plaintext form. For security purposes, the key specified in plaintext form will be stored in encrypted form.

string: Specifies the key. Its plaintext form is a case-sensitive string of 1 to 16 characters. Its encrypted form is a case-sensitive string of 33 to 53 characters.

Usage guidelines

Use this command to enhance BFD session security.

BFD version 0 does not support this command. The configuration does not take effect.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for multihop detection.

Examples

# Configure the simple authentication mode for multihop BFD control packets, setting the authentication key ID to 1 and key to 123456.

<Sysname> system-view

[Sysname] bfd multi-hop authentication-mode simple 1 plain 123456

bfd multi-hop destination-port

Use bfd multi-hop destination-port to configure the destination port number for multihop BFD control packets.

Use undo bfd multi-hop destination-port to restore the default.

Syntax

bfd multi-hop destination-port port-number

undo bfd multi-hop destination-port

Default

The destination port number for multihop BFD control packets is 4784.

Views

System view

Predefined user roles

network-admin

Parameters

port-number: Specifies the destination port number of multihop BFD control packets, 3784 or 4784.

Usage guidelines

IANA assigned port number 4784 to BFD for multihop BFD detection in control packet mode. By default, H3C devices use 4784 as the destination port number for multihop BFD control packets, while devices from other vendors might use 3784. To avoid BFD session establishment failures, make sure the devices on both ends of the BFD session use the same destination port number for multihop BFD control packets.

This command applies to only new multihop BFD sessions in control packet mode.

Examples

# Specify the destination port number for multihop BFD control packets as 3784.

<Sysname> system-view

[Sysname] bfd multi-hop destination-port 3784

bfd multi-hop detect-multiplier

Use bfd multi-hop detect-multiplier to set the multihop detection time multiplier for control packet mode and echo packet mode.

Use undo bfd multi-hop detect-multiplier to restore the default.

Syntax

bfd multi-hop detect-multiplier value

undo bfd multi-hop detect-multiplier

Default

The multihop detection time multiplier for control packet mode and echo packet mode is 5.

Views

System view

Static BFD session view

Predefined user roles

network-admin

Parameters

value: Specifies the multihop detection time multiplier. The value range for this argument is 3 to 50.

Usage guidelines

The detection time multiplier determines the maximum number of concurrent BFD control packets that can be discarded.

Table 2 Actual detection interval calculation method

Mode

Actual detection interval of the sender

Control packetmode BFD session in asynchronous mode

Detection time multiplier of the receiver × MAX (minimum receiving interval supported by the sender, minimum sending interval supported by the receiver)

Control packet mode BFD session in demand mode

Detection time multiplier of the sender × MAX (minimum sending interval supported by the sender, minimum receiving interval supported by the receiver)

 

Only the following static BFD sessions support this command:

·     Static BFD sessions in IPv4 control packet mode used for multihop detection.

·     Static BFD sessions in IPv4 echo packet mode used for multihop detection.

·     Static BFD sessions in IPv6 control packet mode used for multihop detection.

·     Static BFD sessions in IPv6 echo packet mode used for multihop detection.

 Examples

# Set the multihop detection time multiplier to 6 for control mode.

<Sysname> system-view

[Sysname] bfd multi-hop detect-multiplier 6

bfd multi-hop min-echo-receive-interval

Use bfd multi-hop min-echo-receive-interval to set the minimum interval for receiving multihop BFD echo packets.

Use undo bfd multi-hop min-echo-receive-interval to restore the default.

Syntax

bfd multi-hop min-echo-receive-interval interval

undo bfd multi-hop min-echo-receive-interval

Default

The minimum interval for receiving multihop BFD echo packets is 400 milliseconds.

Views

System view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for receiving multihop BFD echo packets, in milliseconds. The value takes 0 or is in the range of 3 to 10000.

Usage guidelines

The interval for receiving multihop BFD echo packets is also the interval for sending multihop BFD echo packets. By executing this command, you can control both the receiving interval and sending interval for multihop BFD echo packets.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for multihop detection.

Examples

# Set the minimum interval for receiving multihop BFD echo packets to 500 milliseconds.

<Sysname> system-view

[Sysname] bfd multi-hop min-echo-receive-interval 500

Related commands

bfd static

bfd multi-hop min-receive-interval

Use bfd multi-hop min-receive-interval to set the minimum interval for receiving multihop BFD control packets.

Use undo bfd multi-hop min-receive-interval to restore the default.

Syntax

bfd multi-hop min-receive-interval interval

undo bfd multi-hop min-receive-interval

Default

The minimum interval for receiving multihop BFD control packets is 400 milliseconds.

Views

System view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for receiving multihop BFD control packets, in milliseconds. The value range for this argument is 3 to 10000.

Usage guidelines

Use this command to prevent the packet sending rate of the peer end from exceeding the packet receiving capability (minimum control packet receiving interval) of the local end. If the receiving capability is exceeded, the peer end dynamically adjusts the BFD control packet sending interval to the minimum control packet receiving interval of the local end.

A static BFD session supports this command only when it is in IPv4 or IPv6 echo packet mode used for multihop detection.

Examples

# Set the minimum interval for receiving multihop BFD control packets to 500 milliseconds.

<Sysname> system-view

[Sysname] bfd multi-hop min-receive-interval 500

bfd multi-hop min-transmit-interval

Use bfd multi-hop min-transmit-interval to set the minimum interval for transmitting multihop BFD control packets.

Use undo bfd multi-hop min-transmit-interval to restore the default.

Syntax

bfd multi-hop min-transmit-interval interval

undo bfd multi-hop min-transmit-interval

Default

The minimum interval for transmitting multihop BFD control packets is 400 milliseconds.

Views

System view

Static BFD session view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for transmitting multihop BFD control packets, in milliseconds. The value range for this argument is 3 to 10000.

Usage guidelines

Use this command to prevent the BFD packet sending rate from exceeding the device capability.

The actual BFD control packet transmitting interval on the local end is the greater value between the following values:

·     Minimum interval for transmitting BFD control packets on the local end.

·     Minimum interval for receiving BFD control packets on the peer end.

A static BFD session supports this command only when it is in IPv4 or IPv6 control packet mode used for multihop detection.

Examples

# Set the minimum interval for transmitting multihop BFD control packets to 500 milliseconds.

<Sysname> system-view

[Sysname] bfd multi-hop min-transmit-interval 500

bfd session init-mode

Use bfd session init-mode to configure the mode for establishing a BFD session.

Use undo bfd session init-mode to restore the default.

Syntax

bfd session init-mode { active | passive }

undo bfd session init-mode

Default

BFD uses the active mode.

Views

System view

Predefined user roles

network-admin

Parameters

active: Specifies the active mode. In active mode, BFD actively transmits BFD control packets to the remote device, regardless of whether it receives a BFD control packet from the remote device.

passive: Specifies the passive mode. In passive mode, BFD does not actively transmit a BFD control packet to the remote end; it transmits a BFD control packet only after receiving a BFD control packet from the remote end.

Usage guidelines

A minimum of one end must operate in active mode for a BFD session to be established.

BFD version 0 does not support this command. The configuration does not take effect.

Examples

# Configure the session establishment mode as passive.

<Sysname> system-view

[Sysname] bfd session init-mode passive

bfd session-negotiation delay-upon-down

Use bfd session-negotiation delay-upon-down to enable session negotiation delay for down BFD sessions and set a delay timer.

Use undo bfd session-negotiation delay-upon-down to restore the default.

 

 

NOTE:

This command is supported only in R5212 and later versions.

 

Syntax

bfd session-negotiation delay-upon-down interval

undo bfd session-negotiation delay-upon-down

Default

Session negotiation delay is disabled for down BFD sessions.

Views

System view

Predefined user roles

network-admin

Parameters

interval: Specifies a delay timer in the range of 1 to 1200 seconds.

Usage guidelines

If an upper-layer protocol uses BFD to detect the active path, an active/standby path switchover is triggered after the active path goes down. If the BFD session comes up before the active path recovers, the traffic on the standby path will be switched over to the active path. In this case, traffic loss will occur.

The session negotiation delay function starts a delay timer for each BFD session when it changes from up to down state and each newly created session. Before the timer expires, the device does not perform session negotiation for the session. The delay timer allows the active path to recover completely before the BFD session comes up again.

Examples

# Enable session negotiation delay for down BFD sessions and set the delay timer to 6 seconds.

<Sysname> system-view

[Sysname] bfd session-negotiation delay-upon-down 6

Related commands

display bfd session

bfd static

Use bfd static to create a static BFD session and enter its view, or enter the view of an existing static BFD session.

Use undo bfd static to delete a static BFD session and all its settings.

Syntax

Static BFD session for single-hop detection with IPv4 control packets:

bfd static session-name [ peer-ip ipv4-address interface interface-type interface-number source-ip ipv4-address ]

undo bfd static session-name

Static BFD session for multihop detection with IPv4 control packets:

bfd static session-name [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] source-ip ipv4-address [ track-interface interface-type interface-number ] ]

undo bfd static session-name

Static BFD session for single-hop detection with IPv4 echo packets:

bfd static session-name [ peer-ip ipv4-address interface interface-type interface-number destination-ip ipv4-address [ source-ip ipv4-address ] one-arm-echo [ discriminator auto ] ]

undo bfd static session-name

Static BFD session for multihop detection with IPv4 echo packets:

bfd static session-name [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] destination-ip ipv4-address [ source-ip ipv4-address ] one-arm-echo [ discriminator auto ] ]

undo bfd static session-name

Static BFD session for single-hop detection with IPv6 control packets:

bfd static session-name [ peer-ipv6 ipv6-address interface interface-type interface-number source-ipv6 ipv6-address ]

undo bfd static session-name

Static BFD session for multihop detection with IPv6 control packets:

bfd static session-name [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] source-ipv6 ipv6-address [ track-interface interface-type interface-number ] ]

undo bfd static session-name

Static BFD session for single-hop detection with IPv6 echo packets:

bfd static session-name [ peer-ipv6 ipv6-address interface interface-type interface-number destination-ipv6 ipv6-address [ source-ipv6 ipv6-address ] one-arm-echo [ discriminator auto ] ]

undo bfd static session-name

Static BFD session for multihop detection with IPv6 echo packets:

bfd static session-name [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] destination-ipv6 ipv6-address [ source-ipv6 ipv6-address ] one-arm-echo [ discriminator auto ] ]

Static BFD session for single-hop detection with IPv4 control packets (the peer address is fixed at 224.0.0.184):

bfd static session-name [ peer-ip default-ip interface interface-type interface-number source-ip ip-address ]

undo bfd static session-name

Default

No static BFD sessions exist.

Views

System view

Predefined user roles

network-admin

Parameters

session-name: Specifies a static BFD session name, a case-sensitive string of 1 to 64 characters.

peer-ip ipv4-address: Specifies the peer IPv4 address in dotted decimal notation. It must be a valid unicast IPv4 address. For a static BFD session in control packet mode, the peer IPv4 address and the source IPv4 address determine the path to be detected. For a static BFD session in echo packet mode, the peer IPv4 address and the destination IPv4 address determine the path to be detected.

peer-ipv6 ipv6-address: Specifies the peer IPv6 address. For a static BFD session in control packet mode, the peer IPv6 address and the source IPv6 address determine the path to be detected. For a static BFD session in echo packet mode, the peer IPv6 address and the destination IPv6 address determine the path to be detected.

default-ip: Specifies the peer IPv4 address as 224.0.0.184.

vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the static BFD session belongs to the public network.

interface interface-type interface-number: Specifies an interface by its type and number. BFD uses the specified interface as the outgoing interface for outgoing packets.

destination-ip ipv4-address: Specifies the destination IPv4 address for echo packets, in dotted decimal notation. It must be a valid unicast IPv4 address of the local end.

destination-ipv6 ipv6-address: Specifies the destination IPv6 address for echo packets. It must be the IPv6 address of the local end.

source-ip ipv4-address: Specifies the source IPv4 address for BFD packets, in dotted decimal notation. It must be a valid unicast IPv4 address.

source-ipv6 ipv6-address: Specifies the source IPv6 address for BFD packets.

one-arm-echo: Specifies the static BFD session mode as echo packet mode.

discriminator: Specifies BFD session discriminators.

auto: Enables the device to automatically assign local discriminator values to static BFD sessions.

track-interface interface-type interface-number: Specifies an interface monitored by the static BFD session. When the monitored interface fails, the static BFD session changes to the down state. If you do not specify this option, the static BFD session does not monitor any interfaces.

Usage guidelines

A static BFD session can be used for single-hop detection and multihop detection. By working with Track, a static BFD session can provide fast failure detection. For more information about Track association with BFD, see Track in High Availability Configuration Guide.

If a static BFD session in control packet mode is created on the peer device, you must use this command to create a static BFD session on the local device. The BFD session discriminators must match on the local and peer devices. For example, if you execute the bfd static abc peer-ip 20.1.1.1 source-ip 20.1.1.2 command in system view and the discriminator local 513 and discriminator remote 514 commands in static BFD session on the local device, you must execute the bfd static abc peer-ip 20.1.1.2 source-ip 20.1.1.1 command and the discriminator local 514 and discriminator remote 513 commands on the peer device.

When creating a static BFD session, you must specify a peer IP address. The system checks only the format of the IP address but not its correctness. If the peer IPv4 or IPv6 address is incorrect, the static BFD session cannot be established. The bfd static session-name command without any parameters specified can only be used to enter the view of an existing static BFD session.

For a static BFD session in control packet mode, you must use the discriminator command to specify its local and remote discriminators. Otherwise, the static BFD session does not take effect.

You need to create a static BFD session on only the local device if you use the echo packet mode for detection. As a best practice, specify the source IP address for echo packets when creating a static BFD session. Make sure the specified source IP address does not belong to the subnet where a local interface resides. Without a source IP address specified, the device uses the IP address specified in the bfd echo-source-ip or bfd echo-source-ipv6 command as the source IP address of echo packets. If you do not specify the source IP address by using either method, the device uses the IP address specified in the destination-ip or destination-ipv6 command as the source IP address of echo packets.

To use a static BFD session in control packet mode for single-hop detection, you must perform the following configuration:

·     Specify the IP address of the peer interface for the peer-ip/peer-ipv6 keyword.

·     Specify the IP address of the local interface for the source-ip/source-ipv6 keyword.

For a static BFD session in control packet mode, the source IP address of BFD packets is the IP address specified for the source-ip/source-ipv6 keyword, and the destination IP address is the IP address specified for the peer-ip/peer-ipv6 keyword.

For a static BFD session in echo packet mode, the source IP address of BFD packets is the IP address specified for the source-ip/source-ipv6 keyword, and the destination IP address is the IP address specified for the destination-ip/destination-ipv6 keyword. If no source IP address is specified, the device uses the IP address specified in the destination-ip or destination-ipv6 command as the source IP address of echo packets.

To modify a static BFD session, delete the static BFD session and then configure a new static BFD session.

Different static BFD sessions cannot have the same local discriminator.

To detect data link layer connectivity for an interface, execute one of the following commands:

·     bfd detect-interface source-ip

·     bfd static session-name peer-ip default-ip interface interface-type interface-number source-ip ip-address

Use the IP address of the interface as the source IP address. If the interface does not have an IP address, specify a unicast IP address other than 0.0.0.0. An interface can use only one static BFD session to detect data link layer connectivity.

In a VPN VPWS dual-homed network, when the AC of a DF fails, the BDF cannot quickly detect the failure to take over. To solve this problem, you can configure a static BFD session on the DF to monitor the AC state and execute the evpn track bfd command on the BDF. The takeover process occurs as follows:

1.     When the AC of the DF fails, the DF sets the static BFD session to the down state and notifies the BDF.

2.     The BDF quickly takes over as the DF, which minimizes packet loss.

For more information about EVPN VPWS networking and DF election, see EVPN VPWS configuration in EVPN Configuration Guide.

A static BFD session can monitor the following interfaces:

·     Layer 2 Ethernet interfaces.

·     Layer 3 Ethernet interfaces and their subinterfaces.

·     Layer 2 aggregate interfaces and their member ports.

·     Layer 3 aggregate interfaces and their subinterfaces and member ports.

Examples

# Create a static BFD session and enter its view. The static BFD session detects the path between 1.1.1.1 and 1.1.1.2 and uses HundredGigE 1/0/1 to send BFD packets with source IP address 1.1.1.1 and destination IP address is 1.1.1.2. The local discriminator is 1537, and the remote discriminator is 2048.

<Sysname> system-view

[Sysname] bfd static abc peer-ip 1.1.1.2 interface hundredgige 1/0/1 source-ip 1.1.1.1

[Sysname-bfd-static-session-abc] discriminator local 1537

[Sysname-bfd-static-session-abc] discriminator remote 2048

# Create a static BFD session in echo mode and enter its view. The static BFD session detects the path between 1.1.1.1 and 1.1.1.2 and uses HundredGigE 1/0/1 to send BFD packets with source IP address 9.9.9.9 and destination IP address is 1.1.1.2.

<Sysname> system-view

[Sysname] bfd static abc peer-ip 1.1.1.1 interface hundredgige 1/0/1 destination-ip 1.1.1.2 source-ip 9.9.9.9 one-arm-echo discriminator auto

[Sysname-bfd-static-session-abc]

Related commands

bfd detect-interface source-ip

bfd echo-source-ip

bfd echo-source-ipv6

discriminator

bfd template

Use bfd template to create a BFD template and enter its view, or enter the view of an existing BFD template.

Use undo bfd template to delete the BFD template.

Syntax

bfd template template-name

undo bfd template template-name

Default

No BFD templates exist.

Views

System view

Predefined user roles

network-admin

Parameters

template-name: Specifies the template name, a case-sensitive string of 1 to 63 characters.

Examples

# Create BFD template bfd1 and enter BFD template view.

<Sysname> system-view

[Sysname] bfd template bfd1

[Sysname-bfd-template-bfd1]

discriminator

Use discriminator to specify the local and remote discriminators for a static BFD session.

Use undo discriminator to remove the local and remote discriminator for the static BFD session.

Syntax

discriminator { local local-value | remote remote-value }

undo discriminator { local local-value | remote remote-value }

Default

No local and remote discriminators are specified for a static BFD session.

Views

Static BFD session view

Predefined user roles

network-admin

Parameters

local local-value: Specifies the local discriminator in the range of 1 to 32768.

remote remote-value: Specifies the remote discriminator in the range of 1 to 4294967295.

Usage guidelines

Use this command only if you do not specify the local or remote discriminator when creating a static BFD session.

To modify the local or remote discriminator of a static BFD session, execute the undo discriminator and then the discriminator command to specify a new local or remote discriminator.

Different static BFD sessions cannot have the same local discriminator.

Examples

# Create local discriminator 1537 and remote discriminator 2048 for static BFD session abc.

<Sysname> system-view

[Sysname] bfd static abc

[Sysname-bfd-static-session-abc] discriminator local 1537

[Sysname-bfd-static-session-abc] discriminator remote 2048

Related commands

bfd static

display bfd session

Use display bfd session to display BFD session information.

Syntax

display bfd session [ discriminator local-value | discriminator local local-value | static name session-name | verbose ]

display bfd session [ [ dynamic ] [ control | echo ] [ ip ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ip { ipv4-address | default-ip } [ vpn-instance vpn-instance-name ] ] [ verbose ] ]

display bfd session [ [ dynamic ] [ control | echo ] [ ipv6 ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] ] [ verbose ] ]

display bfd session [ [ dynamic ] [ control | echo ] [ lsp | te | pw | srv6-policy ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ [ peer-ip ipv4-address [ vpn-instance vpn-instance-name ] ] | [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] ] ] [ verbose ] ]

display bfd session [ [ static ] [ ip ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ip { ipv4-address | default-ip } [ vpn-instance vpn-instance-name ] ] [ verbose ]

display bfd session [ [ static ] [ ipv6 ] [ state { admin-down | down | init | up } ] [ discriminator remote remote-value ] [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] ] [ verbose ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

discriminator local-value: Specifies a BFD session by its local discriminator in the range of 1 to 4294967295. If you do not specify a BFD session, this command displays information about all BFD sessions.

discriminator local local-value: Specifies a BFD session by its local discriminator in the range of 1 to 4294967295. If you do not specify a BFD session, this command displays information about all BFD sessions.

name session-name: Specifies a static BFD session by its name, a case-sensitive string of 1 to 15 characters.

dynamic: Specifies dynamic BFD sessions.

static: Specifies static BFD sessions.

control: Specifies BFD sessions in control packet mode.

echo: Specifies BFD sessions in echo mode.

ip: Specifies BFD sessions used to detect IPv4 links.

ipv6: Specifies BFD sessions used to detect IPv6 links.

lsp: Specifies BFD sessions used to detect MPLS LSPs.

te: Specifies BFD sessions used to detect MPLS TE tunnels.

pw: Specifies BFD sessions used to detect PWs.

srv6-policy: Specifies BFD sessions used to detect SRv6 policies.

state: Displays BFD sessions by session state.

down: Specifies BFD sessions in Down state.

admin-down: Specifies BFD sessions in AdminDown state.

init: Specifies BFD sessions in Init state.

up: Specifies BFD sessions in Up state.

discriminator remote remote-value: Specifies a BFD session by its remote discriminator  in the range of 1 to 4294967295.

peer-ip ipv4-address: Specifies a BFD session by the peer IPv4 address in dotted decimal notation.

peer-ipv6 ipv6-address: Specifies a BFD session by the peer IPv6 address.

default-ip: Specifies the peer IPv4 address as 224.0.0.184.

vpn-instance vpn-instance-name: Specifies an MPLS L3VPN instance by its name, a case-sensitive string of 1 to 31 characters. If you do not specify this option, the command displays the BFD sessions of the public network.

verbose: Displays detailed BFD session information. If you do not specify this keyword, the command displays brief BFD session information.

Usage guidelines

If you do not specify the dynamic or static keyword, this command displays all dynamic and static BFD sessions.

The discriminator local-value and discriminator local local-value parameters have the same effect. The only difference is that you do not need to enter local when using the latter.

Examples

# Display brief information about all BFD sessions.

<Sysname> display bfd session

 Total Session Num: 4     Up Session Num: 4     Init Mode: Active

 

 IPv4 session working in control mode:

 

 LD              SourceAddr      DestAddr        State  Running Up for Holdtime

   Interface

 513/513         1.1.1.1         1.1.1.2         Up     00:00:20       2297ms

   HGE1/0/1

 

 IPv6 session working in control mode:

 

       Local discr: 513                  Remote discr: 513

         Source IP: FE80::20C:29FF:FED4:7171

    Destination IP: FE80::20C:29FF:FE72:AC4D

     Session state: Up                      Interface: HGE1/0/2

         Hold time: 2142ms             Running Up for: 00:05:22

 

 IPv4 static session working in echo packet mode:

 

 LD/RD           SourceAddr      DestAddr        State  Running Up for Holdtime

   Interface

 327             192.168.1.101   192.168.1.83    Up     00:00:20       2050ms

   HGE1/0/1

 

 MPLS LSP session working in control packet mode:

 

 LD/RD           SourceIP        DestinationIP   State   Holdtime    Interface

 32769/32769     2.2.2.9         127.0.0.1       Up      4990ms      N/A

 

 MPLS TE session working in echo mode:

 

 LD              SourceIP        DestinationIP   State   Holdtime    Interface

 32777           1.1.1.1         3.3.3.3         Up      4430ms      Tun0

Table 3 Command output

Field

Description

Total Session Num

Total number of BFD sessions.

Up Session Num

Total number of active BFD sessions.

Init Mode

BFD operating mode: Active or passive.

XX session working in yy mode

BFD session type and operating mode:

·     IPv4 session working in control mode—IPv4 session in control mode.

·     IPv4 session working in echo mode.

·     IPv6 session working in control mode—IPv6 session in control mode.

·     IPv6 session working in echo mode.

·     IPv4 static session working in control packet mode.

·     IPv6 static session working in control packet mode.

·     MPLS LSP session working in control packet mode—BFD session in control mode used to detect failures in an LSP.

·     MPLS LSP session working in echo mode—BFD session in echo mode used to detect failures in an LSP.

·     MPLS TE session working in control packet mode.

·     MPLS TE session working in echo mode.

·     IPv6 SR policy session working in echo mode—BFD session in echo mode used to detect failures in an SRv6 tunnel.

·     IPv4 SDWAN session working in control packet mode.

·     IPv6 SDWAN session working in control packet mode.

·     IPv6 TE policy session working in echo mode.

LD/RD

Local discriminator/Remote discriminator of the session.

SourceAddr

Source IPv4 address of the session.

DestAddr

Destination IPv4 address of the session.

State

Session state: Down, Init, Adown, or Up.

Holdtime

Length of time before session detection timer expires.

For a BFD session in Down state, this field displays 0ms.

Interface

Name of the interface of the session.

Local discr

Local discriminator of the session.

Remote discr

Remote discriminator of the session.

Source IP

Source IPv6 address of the session.

Destination IP

Destination IPv6 address of the session.

Session state

Session state: Down, Adown, Init, or Up.

Running Up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

Hold time

Length of time before session detection timer expires.

For a BFD session in Down state, this field displays 0ms.

# Display detailed BFD session information.

<Sysname> display bfd session verbose

 Total Session Num: 4     Up Session Num: 4     Init Mode: Active

 

 IPv4 session working in control mode:

 

       Local Discr: 513                  Remote Discr: 513

         Source IP: 1.1.1.1            Destination IP: 1.1.1.2

  Destination port: 3784                Session State: Up

         Interface: HundredGigE1/0/1

      Min Tx Inter: 500ms                Act Tx Inter: 500ms

      Min Rx Inter: 500ms                Detect Inter: 2500ms

          Rx Count: 42                       Tx Count: 43

      Connect Type: Direct             Running Up for: 00:00:20

         Hold Time: 2078ms                  Auth mode: None

       Detect Mode: Async                        Slot: 0

          Protocol: OSPF

           Version: 1

         Diag Info: No Diagnostic

 

 IPv6 session working in control mode:

 

       Local Discr: 513                  Remote Discr: 513

         Source IP: FE80::20C:29FF:FED4:7171

    Destination IP: FE80::20C:29FF:FE72:AC4D

  Destination port: 3784                Session State: Up

         Interface: HundredGigE1/0/2

      Min Tx Inter: 500ms                Act Tx Inter: 500ms

      Min Rx Inter: 500ms                Detect Inter: 2500ms

          Rx Count: 38                       Tx Count: 38

      Connect Type: Direct             Running Up for: 00:07:01

         Hold Time: 2211ms                  Auth Mode: None

       Detect Mode: Async                        Slot: 0

          Protocol: OSPFv3

           Version: 1

         Diag Info: No Diagnostic

 

 IPv4 session working in control mode:

      Session name: abc

       Local Discr: 310                  Remote Discr: 308

         Source IP: 12.1.1.1           Destination IP: 12.1.1.2

  Destination port: 3784                Session State: Up

         Interface: HundredGigE1/0/1

      Min Tx Inter: 500ms                Act Tx Inter: 500ms

      Min Rx Inter: 500ms                Detect Inter: 2500ms

          Rx Count: 514                      Tx Count: 514

      Connect Type: Direct             Running Up for: 00:07:01

         Hold Time: 2120ms                  Auth Mode: None

       Detect Mode: Async                        Slot: 0

          Protocol: STATIC_IPv4

           Version: 1

         Diag Info: No Diagnostic

 

 IPv6 session working in control mode:

      Session name: bbbb

       Local Discr: 1700                 Remote Discr: 1700

         Source IP: FE80::20C:29FF:FED4:7171

    Destination IP: FE80::20C:29FF:FE72:AC4D

  Destination port: 3784                Session State: Up

         Interface: HundredGigE1/0/2

      Min Tx Inter: 500ms                Act Tx Inter: 500ms

      Min Rx Inter: 500ms                Detect Inter: 2500ms

          Rx Count: 38                       Tx Count: 38

      Connect Type: Direct             Running Up for: 00:12:01

         Hold Time: 2211ms                  Auth Mode: None

       Detect Mode: Async                        Slot: 0

          Protocol: STATIC_IPv6

           Version: 1

         Diag Info: No Diagnostic

Table 4 Command output

Field

Description

Total Session Num

Total number of BFD sessions.

Up Session Num

Total number of active BFD sessions.

Init Mode

BFD operating mode: Active or passive.

XX session working in yy mode

BFD session type and operating mode:

·     IPv4 session working in control mode—IPv4 session in control mode.

·     IPv4 session working in echo mode.

·     IPv6 session working in control mode—IPv6 session in control mode.

·     IPv6 session working in echo mode.

·     IPv4 static session working in control packet mode.

·     IPv6 static session working in control packet mode.

·     MPLS LSP session working in control packet mode—BFD session in control mode used to detect failures in an LSP.

·     MPLS LSP session working in echo mode—BFD session in echo mode used to detect failures in an LSP.

·     MPLS TE session working in control packet mode.

·     MPLS TE session working in echo mode.

·     IPv6 SR policy session working in echo mode—BFD session in echo mode used to detect failures in an SRv6 tunnel.

·     IPv4 SDWAN session working in control packet mode.

·     IPv6 SDWAN session working in control packet mode.

·     IPv6 TE policy session working in echo mode.

Session name

Static BFD session name. This field appears only for a static BFD session.

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Destination port

Destination port number in BFD packets defined in Comware:

·     The destination port number in single-hop BFD control packets is 3784.

·     The destination port number in single-hop or multihop BFD echo packets is 3785.

·     The destination port number in multihop BFD control packets is 4784.

·     The destination port number in BFD control packets for association between link aggregation and BFD is 6784.

The device uses the destination port number in incoming packets that are not defined in Comware as the destination port number in outgoing BFD packets.

Session State

Session state: Down, Adown, Init, or Up.

Interface

Name of the interface of the session.

Min Tx Inter

Minimum transmit interval.

Min Rx Inter

Minimum receive interval.

Act Tx Inter

Actual transmit interval.

Detect Inter

Actual session detection timer.

Rx Count

Number of packets received.

Tx Count

Number of packets sent.

Hold Time

Length of time before session detection timer expires.

Auth mode

Session authentication mode.

Connect Type

Connection type of the interface: Direct or indirect.

Running up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

Detect Mode

Detection mode:

·     Async—Asynchronous mode.

·     Demand—Demand mode.

·     Async/Echo—Asynchronous mode with echo detection enabled.

·     Demand/Echo—Demand mode with echo detection enabled.

Slot

Slot number of the card where the BFD session resides.

Protocol

Protocol associated with BFD:

·     OSPF.

·     ISIS_BR_L1—IS-IS with the network type as broadcast and the router type as Level 1.

·     ISIS_BR_L2—IS-IS with the network type as broadcast and the router type as Level 2.

·     ISIS_P2P—IS-IS with the network type as P2P.

·     ISIS6_BR_L1—IPv6 IS-IS with the network type as broadcast and the router type as Level 1.

·     ISIS6_BR_L2—IPv6 IS-IS with the network type as broadcast and the router type as Level 2.

·     ISIS6_P2P—IPv6 IS-IS with the network type as P2P.

·     BGP.

·     MPLS_RSVP.

·     STATIC4—IPv4 static routing.

·     TRACK—Track.

·     RIP.

·     IPFRR—FIB IP FRR.

·     MAD.

·     MPLS_LSPV.

·     OSPFv3.

·     BGP4+.

·     PIM.

·     PIM6—IPv6 PIM.

·     STATIC6—IPv6 static routing.

·     RIPNG—RIPng.

·     Interface—Interface state.

·     TUNNEL.

·     VTEP.

·     LAGG—Link aggregation.

·     STATIC_IPv4—IPv4 static BFD session.

·     STATIC_IPv6—IPv6 static BFD session.

·     SDWAN—BFD session for SDWAN tunnels.

Diag Info

Diagnostic information about the session:

·     No Diagnostic.

·     Control Detection Time Expired—A control-mode BFD session goes down because local detection times out.

·     Echo Function Failed—An echo-mode BFD session goes down, because local detection times out or the source IP address of echo packets is deleted.

·     Neighbor Signaled Session Down—The remote end notifies the local end of BFD session down.

·     Administratively Down—The local system prevents a BFD session from being established.

first-fail-timer

Use first-fail-timer to configure the timer that delays reporting the first BFD session establishment failure to the data link layer.

Use undo first-fail-timer to restore the default.

Syntax

first-fail-timer seconds

undo first-fail-timer

Default

The first BFD session establishment failure is not reported to the data link layer.

Views

Static BFD session view

Predefined user roles

network-admin

Parameters

seconds: Specifies the timeout time that reports the first BFD session establishment failure to the data link layer. The value range for this argument is 1 to 10000 seconds.

Usage guidelines

This command takes effect only on static BFD sessions after you configure the process-interface-status command.

If the static BFD session fails to be established when the timer expires, BFD reports the failure to the data link layer and sets the data link layer state of the interface to DOWN(BFD). This behavior rapidly identifies the interfaces for which BFD sessions fail to be established. In this case, the BFD session state is displayed as Down in the display bfd session command output. The line protocol state of the interface is displayed as DOWN(BFD) in the display interface command output.

If you execute the command on the local end, the BFD session for detecting the local interface state fails to be established when the following conditions exist:

·     The command is not executed on the remote end.

·     The local and remote ends have mismatching BFD authentication settings.

Examples

# Configure the timer that delays reporting the first BFD session establishment failure as 100 seconds.

<Sysname> system-view

[Sysname] bfd static abc peer-ip default-ip interface hundredgige 1/0/1 source-ip 10.1.1.1 discriminator local 1 remote 1

[Sysname-bfd-static-session-1] first-fail-timer 100

Related commands

bfd static

display interface (Interface Command Reference)

processing-interface-status

hardware-resource bfd_enhance

Use hardware-resource bfd_enhance to enable or disable BFD optimization.

Syntax

hardware-resource bfd_enhance { enable | disable }

Default

BFD optimization is enabled.

Views

System view

Predefined user roles

network-admin

Parameters

enable: Enables BFD optimization.

disable: Disables BFD optimization.

Examples

# Disable BFD optimization.

<Sysname> system-view

[Sysname] hardware-resource bfd_enhance disable

Do you want to change the specified hardware resource working mode? [Y/N]: y

The hardware resource working mode is changed.

process-interface-status

Use process-interface-status to associate the interface state with a static BFD session.

Use undo process-interface-status to restore the default.

Syntax

process-interface-status

undo process-interface-status

Default

The state of a static BFD session does not affect the state of the data link layer of the interface.

Views

Static BFD session view

Predefined user roles

network-admin

Usage guidelines

This command enables a static BFD session with peer address 224.0.0.184 to set the link layer protocol of the interface to DOWN(BFD) when detecting a link failure. To display information about the link layer protocol state, use the display interface command.

Examples

# Associate the state of HundredGigE 1/0/1 with static BFD session abc.

<Sysname> system-view

[Sysname] interface gigabitethernet 1/0/1

[Sysname] bfd static abc peer-ip default-ip interface hundredgige 1/0/1 source-ip 10.1.1.1 discriminator local 1 remote 1

[Sysname-bfd-static-session-abc] process-interface-status

Related commands

bfd static

display interface

reset bfd session statistics

Use reset bfd session statistics to clear the BFD session statistics.

Syntax

reset bfd session statistics

Views

User view

Predefined user roles

network-admin

Examples

# Clear the BFD session statistics.

<Sysname> reset bfd session statistics

snmp-agent trap enable bfd

Use snmp-agent trap enable bfd to enable SNMP notifications for BFD.

Use undo snmp-agent trap enable bfd to disable SNMP notifications for BFD.

Syntax

snmp-agent trap enable bfd

undo snmp-agent trap enable bfd

Default

All SNMP notifications are enabled for BFD.

Views

System view

Predefined user roles

network-admin

Usage guidelines

To report critical BFD events to an NMS, enable SNMP notifications for BFD. For BFD event notifications to be sent correctly, you must also configure SNMP as described in the network management and monitoring configuration guide for the device.

Examples

# Disable SNMP notifications for BFD.

<Sysname> system-view

[Sysname] undo snmp-agent trap enable bfd

special-processing

Use special-processing to enable special processing for a static BFD session used to detect data link layer connectivity.

Use undo special-processing to disable special processing for the static BFD session.

Syntax

special-processing [ admin-down | authentication-change | session-up ] *

undo special-processing [ admin-down | authentication-change | session-up ] *

Default

All types of special processing are disabled for a static BFD session used to detect data link layer connectivity.

Views

Static BFD session view

Predefined user roles

network-admin

Parameters

admin-down: Notifies a session down event to the data link layer upon receipt of a BFD packet with the State field as AdminDown. This keyword helps rapidly discover interfaces on which BFD sessions are manually shut down. If you do not specify this keyword, the device sets the BFD session state to Down, but does not notify the session down event to the data link layer.

authentication-change: Immediately sets the session to down state upon a local authentication information change. This keyword helps rapidly discover interfaces with authentication information changes. If you do not specify this keyword, the device sets the session to down state if authentication information inconsistency still persists after a period of time.

session-up: Ignores authentication information inconsistency when the local session is up. If a large number of BFD sessions exist, examining authentication information consistency affects device performance. If you do not specify this keyword, the device examines authentication information in incoming BFD packets when the local session state is up. If the authentication information does not match on the two ends, the BFD session is declared down.

Usage guidelines

If you do not specify any parameters, this command enables or disables all types of special processing.

Examples

# Enable all types of special processing for a static BFD session whose outgoing interface is HundredGigE 1/0/1.

<Sysname> system-view

[Sysname] bfd static abc peer-ip default-ip interface hundredgige 1/0/1 source-ip 10.1.1.1 discriminator local 1 remote 1

[Sysname-bfd-static-session-1] special-processing

Related commands

bfd static

process-interface-status

SBFD commands

bfd detect-multiplier

Use bfd detect-multiplier to set the detection time multiplier in BFD template view.

Use undo bfd detect-multiplier to restore the default.

Syntax

bfd detect-multiplier value

undo bfd detect-multiplier

Default

The detection time multiplier is 5.

Views

BFD template view

Predefined user roles

network-admin

Parameters

value: Specifies a detection time multiplier. The value range for this argument is 3 to 50.

Usage guidelines

The detection time multiplier determines the maximum number of SBFD control packets that an initiator can discard continuously.

The detection time is the detection time multiplier of the initiator multiplied by the minimum SBFD packet sending interval of the initiator.

Examples

# In BFD template abc, set the detection time multiplier to 6.

<Sysname> system-view

[Sysname] bfd template abc

[Sysname-bfd-template-abc] bfd detect-multiplier 6

bfd min-transmit-interval

Use bfd min-transmit-interval to set the minimum interval for transmitting SBFD control packets in BFD template view.

Use undo bfd min-transmit-interval to restore the default.

Syntax

bfd min-transmit-interval interval

undo bfd min-transmit-interval

Default

The minimum interval for transmitting SBFD control packets is 400 milliseconds.

Views

BFD template view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for transmitting SBFD control packets, in milliseconds. The value range for this argument is 3 to 10000

Usage guidelines

Use this command to prevent the SBFD control packet sending rate from exceeding the device capability.

The actual SBFD control packet transmitting interval is the set minimum interval.

Examples

# In BFD template abc, set the minimum interval for transmitting SBFD control packets to 500 milliseconds.

<Sysname> system-view

[Sysname] bfd template abc

[Sysname-bfd-template-abc] bfd min-transmit-interval 500

Related commands

bfd detect-multiplier

bfd multi-hop detect-multiplier

Use bfd multi-hop detect-multiplier to set the detection time multiplier in system view.

Use undo bfd multi-hop detect-multiplier to restore the default.

Syntax

bfd multi-hop detect-multiplier value

undo bfd multi-hop detect-multiplier

Default

The detection time multiplier is 5.

Views

System view

Predefined user roles

network-admin

Parameters

value: Specifies a detection time multiplier. The value range for this argument is 3 to 50.

Usage guidelines

The detection time multiplier determines the maximum number of SBFD control packets that an initiator can discard continuously.

The detection time is the detection time multiplier of the initiator multiplied by the minimum SBFD packet sending interval of the initiator.

Examples

# Set the detection time multiplier to 6.

<Sysname> system-view

[Sysname] bfd multi-hop detect-multiplier 6

bfd multi-hop min-transmit-interval

Use bfd multi-hop min-transmit-interval to set the minimum interval for transmitting SBFD control packets in system view.

Use undo bfd multi-hop min-transmit-interval to restore the default.

Syntax

bfd multi-hop min-transmit-interval interval

undo bfd multi-hop min-transmit-interval

Default

The minimum interval for transmitting SBFD control packets is 400 milliseconds.

Views

System view

Predefined user roles

network-admin

Parameters

interval: Specifies the minimum interval for transmitting SBFD control packets, in milliseconds. The value range for this argument is 3 to 10000.

Usage guidelines

Use this command to prevent the SBFD control packet sending rate from exceeding the device capability.

The actual SBFD control packet transmitting interval is the set minimum interval.

Examples

# Set the minimum interval for transmitting SBFD control packets to 500 milliseconds.

<Sysname> system-view

[Sysname] bfd multi-hop min-transmit-interval 500

bfd session-negotiation delay-upon-down

Use bfd session-negotiation delay-upon-down to enable session negotiation delay for down SBFD sessions and set a delay timer.

Use undo bfd session-negotiation delay-upon-down to restore the default.

 

 

NOTE:

This command is supported only in R5212P01 and later versions.

 

Syntax

bfd session-negotiation delay-upon-down interval

undo bfd session-negotiation delay-upon-down

Default

Session negotiation delay is disabled for down SBFD sessions.

Views

System view

Predefined user roles

network-admin

Parameters

interval: Specifies a delay timer in the range of 1 to 1200 seconds.

Usage guidelines

If an upper-layer protocol uses SBFD to detect the active path, an active/standby path switchover is triggered after the active path goes down. If the SBFD session comes up before the active path recovers, the traffic on the standby path will be switched over to the active path. In this case, traffic loss will occur.

The session negotiation delay function starts a delay timer for each SBFD session when it changes from up to down state and each newly created session. Before the timer expires, the device does not perform session negotiation for the session. The delay timer allows the active path to recover completely before the SBFD session comes up again.

Examples

# Enable session negotiation delay for down SBFD sessions and set the delay timer to 6 seconds.

<Sysname> system-view

[Sysname] bfd session-negotiation delay-upon-down 6

Related commands

display bfd session

bfd template

Use bfd template to create a BFD template and enter its view, or enter the view of an existing BFD template.

Use undo bfd template to delete the BFD template.

Syntax

bfd template template-name

undo bfd template template-name

Default

No BFD templates exist.

Views

System view

Predefined user roles

network-admin

Parameters

template-name: Specifies the template name, a case-sensitive string of 1 to 63 characters.

Examples

# Create BFD template bfd1 and enter BFD template view.

<Sysname> system-view

[Sysname] bfd template bfd1

[Sysname-bfd-template-bfd1]

display sbfd session

Use display sbfd session to display SBFD session information.

Syntax

display sbfd session { initiator [ discriminator value | [ ipv6 [ peer-ipv6 ipv6-address ] | srv6-policy ] [ verbose ] | verbose ] | reflector [ discriminator value | verbose ] }

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

initiator: Displays SBFD session information for the initiator.

reflector: Displays SBFD session information for the reflector.

discriminator value: Specifies a local discriminator in the range of 1 to 4294967295.

ipv6: Specifies SBFD sessions used to detect IPv6 links.

peer-ipv6 ipv6-address: Specifies a SBFD session by the peer IPv6 address.

srv6-policy: Specifies SBFD sessions used to detect SRv6 TE policies.

verbose: Displays detailed information about all SBFD sessions. If you do not specify this keyword, the command displays brief information about all SBFD sessions.

Usage guidelines

If you do not specify any keyword, this command displays brief information about all SBFD sessions.

Examples

# Display brief information about all SBFD sessions for the initiator.

<Sysname> display sbfd session intiator

 Total Session Num: 1     Up Session Num: 1

 

 SBFD session (MPLS LSP):

 

       Local Discr: 1                    Remote Discr: 1000001

         Source IP: 1.1.1.1

    Destination IP: 127.0.0.1

     Session State: Up                      Hold Time: 2184ms

    Running Up for: 00:00:00

Table 5 Command output

Field

Description

Total Session Num

Total number of SBFD sessions.

Up Session Num

Number of active SBFD sessions.

SBFD session (xxx)

Path to be detected by the SBFD session:

·     MPLS LSP.

·     SRv6 TE policy.

·     IPv6—IPv6 link.

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Session State

Session state: Down or Up.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

Running up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

# Display detailed information about the SBFD session with local discriminator 2 for the initiator.

<Sysname> display sbfd session initiator discriminator 2

       Local Discr: 2                    Remote Discr: 1000002

         Source IP: 1.1.1.2            Destination IP: 127.0.0.2

     Session State: Up                      Hold Time: 4130ms

      Min Tx Inter: 500ms                Act Tx Inter: 1000ms

      Detect Inter: 5000ms             Running Up for: 00:01:30

          Rx Count: 100                      Tx Count: 100

              Slot: 0                             NID: 22020097

          Protocol: MPLS_LSPV

         Diag Info: No Diagnostic

     Template Name: abc

Table 6 Command output

Field

Description

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Session State

Session state: Down or Up.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

Min Tx Inter

Minimum SBFD packet transmission interval in milliseconds.

Act Tx Inter

Actual SBFD packet transmission interval in milliseconds.

Detect Inter

Actual session detection timer in milliseconds.

Running up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

Rx Count

Number of packets received.

Tx Count

Number of packets sent.

Slot

Slot number of the card where the BFD session resides.

NID

Forwarding entry index of the SID list. This field is displayed only when the index exists and is a non-zero value.

Diag Info

Diagnostic information about the session:

·     No Diagnostic.

·     Control Detection Time Expired—The SBFD session goes down because local detection times out.

·     Neighbor Signaled Session Down—The remote end notifies the local end of SBFD session down.

·     Concatenated Path Down—The SBFD session goes down because the concatenated path associated with the session fails.

Template Name

Template associated with the session. If no template is associated, this field is not displayed.

# Display detailed information about all SBFD sessions for the initiator.

<Sysname> display sbfd session initiator verbose

 Total Session Num: 1     Up Session Num: 1

 

 SBFD session (MPLS LSP):

       Local Discr: 1                    Remote Discr: 1000001

         Source IP: 1.1.1.1            Destination IP: 127.0.0.1

     Session State: Up                      Hold Time: 4130ms

      Min Tx Inter: 500ms                Act Tx Inter: 1000ms

      Detect Inter: 5000ms             Running Up for: 00:01:30

          Rx Count: 100                      Tx Count: 100

              Slot: 0                             NID: 22020097

          Protocol: MPLS_LSPV

         Diag Info: No Diagnostic

     Template Name: abc

Table 7 Command output

Field

Description

Total Session Num

Total number of SBFD sessions.

Up Session Num

Number of active SBFD sessions.

SBFD session (xxx)

Path to be detected by the SBFD session:

·     MPLS LSP.

·     SRv6 TE policy.

·     IPv6—IPv6 link.

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Session State

Session state: Down or Up.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

Min Tx Inter

Minimum SBFD packet transmission interval.

Act Tx Inter

Actual SBFD packet transmission interval.

Detect Inter

Actual session detection timer.

Running up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

Rx Count

Number of packets received.

Tx Count

Number of packets sent.

Slot

Slot number of the card where the BFD session resides.

NID

Forwarding entry index of the SID list. This field is displayed only when the index exists and is a non-zero value.

Diag Info

Diagnostic information about the session:

·     No Diagnostic.

·     Control Detection Time Expired—The SBFD session goes down because local detection times out.

·     Neighbor Signaled Session Down—The remote end notifies the local end of SBFD session down.

·     Concatenated Path Down—The SBFD session goes down because the concatenated path associated with the session fails.

Template Name

Template associated with the session. If no template is associated, this field is not displayed.

# Display brief information about all SBFD sessions for the reflector.

<Sysname> display sbfd session reflector

 

 Local discriminator 1000001 on slot 0

 Configured mode: Explicit value

  Total Session Num: 1

 

        Local Discr: 1000001                  Remote Discr: 1

          Source IP: 2.2.2.1

     Destination IP: 1.1.1.1

          Hold Time: 2200ms

           VRF Name: vpn1

Table 8 Command output

Field

Description

Configured mode

Discriminator type:

·     IP Address—IPv4 address.

·     Explicit Value—Integer.

Total Session Num

Total number of SBFD sessions.

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

VRF Name

VPN instance bound to the interface where the packets of the SBFD session are received.

If no VPN instance is bound to the interface, this field displays a hyphen (-).

# Display detailed information about the SBFD session with local discriminator 1000001 for the reflector.

<Sysname> display sbfd session reflector discriminator 1000001

 

 Local discriminator 1000001 on slot 0

 Configured mode: IP Address

 Total Session Num: 2

 

       Local Discr: 1000001              Remote Discr: 1

         Source IP: 2.2.2.1            Destination IP: 1.1.1.1

      Min Tx Inter: 500ms                Min Rx Inter: 10ms

      Detect Multi: 5                  Running Up for: 00:02:30

          Rx Count: 100                      Tx Count: 100

     Max Rx Period: 498ms               Max Tx Period: 1280us

         Hold Time: 2200ms

          VRF Name: vpn1

 

      Local Discr: 1000001              Remote Discr: 2

         Source IP: 2.2.2.2            Destination IP: 1.1.1.2

      Min Tx Inter: 1000ms               Min Rx Inter: 3790ms

      Detect Multi: 5                  Running Up for: 00:10:59

          Rx Count: 123                      Tx Count: 122

     Max Rx Period: 980ms               Max Tx Period: 580us

         Hold Time: 2500ms

          VRF Name: vpn2

Table 9 Command output

Field

Description

Configured mode

Discriminator type:

·     IP Address—IPv4 address.

·     Explicit Value—Integer.

Total Session Num

Total number of SBFD sessions.

Local Discr

Local discriminator of the session.

Remote Discr

Remote discriminator of the session.

Source IP

Source IP address of the session.

Destination IP

Destination IP address of the session.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

Min Tx Inter

Minimum transmission interval of incoming SBFD packets.

Min Rx Inter

Minimum SBFD packet receiving interval.

Detect Multi

Session detection time multiplier carried in incoming SBFD packets.

Running up for

Duration for which the session remains up, in the format of hh:mm:ss, where hh, mm, and ss represent the hours, minutes, and seconds, separately.

Rx Count

Number of packets received.

Tx Count

Number of packets sent.

Max Rx Period

Maximum SBFD packet receiving interval in milliseconds.

Max Tx Period

Maximum response packet transmission interval, in microseconds.

Hold Time

Length of time before the session detection timer expires, in milliseconds.

For an SBFD session in Down state, this field displays 0ms.

VRF Name

VPN instance bound to the interface where the packets of the SBFD session are received.

If no VPN instance is bound to the interface, this field displays a hyphen (-).

Related commands

sbfd local-discriminator

sbfd destination ipv4 remote-discriminator

Use sbfd destination ipv4 remote-discriminator to associate the destination IPv4 address of the detected path with the remote discriminator of the SBFD session for the initiator.

Use undo sbfd destination ipv4 to cancel the association between the destination IPv4 address of the detected path and the remote discriminator of the SBFD session for the initiator.

Syntax

sbfd destination ipv4 destination-ipv4-address remote-discriminator { ipv4-address | integer-value }

undo sbfd destination ipv4 destination-ipv4-address

Default

The destination IPv4 address of the detected path is not associated with the remote discriminator of the SBFD session for the initiator.

Views

System view

Predefined user roles

network-admin

Parameters

destination-ipv4-address: Specifies a valid unicast IPv4 address as the destination IPv4 address of the detected path.

ipv4-address: Specifies a valid unicast IPv4 address as the remote discriminator.

integer-value: Specifies an integer as the remote discriminator. The value range for this argument is 1 to 4294967295.

Usage guidelines

This command allows you to use the specified remote discriminator for an SBFD session to detect an LSP, MPLS TE tunnel, or SR-MPLS TE policy.

The initiator selects a remote discriminator for an SBFD session as follows:

1.     Selects the remote discriminator of the SBFD session used for path connectivity detection. For example, the remote discriminator of the SBFD session specified in the mpls sbfd command.

2.     Selects the remote discriminator specified in this command.

3.     Selects the destination IPv4 address of the detected path. For example, when you use SBFD to detect an SR-MPLS TE policy, the endpoint address is used as the remote discriminator of the SBFD session.

You can execute this command repeatedly to configure multiple associations between destination IPv4 addresses and remote discriminators for the initiator.

When configuring or canceling an association, the SBFD session might flap if it is in up state.

Examples

# Associate destination IPv4 address 22.22.2.2/32 of the detected LSP with remote discriminator 1.1.1.1 of the SBFD session for the initiator.

<Sysname> system-view

[Sysname] mpls bfd enable

[Sysname] mpls sbfd 22.22.2.2 32

[Sysname] sbfd destination ipv4 22.22.2.2 remote-discriminator 1.1.1.1

Related commands

mpls bfd (MPLS Command Reference)

sbfd (Segment Routing Command Reference)

sbfd local-discriminator

sr-policy sbfd enable (Segment Routing Command Reference)

sbfd destination ipv6 remote-discriminator

Use sbfd destination ipv6 remote-discriminator to associate the destination IPv6 address of the detected path with the remote discriminator of the SBFD session for the initiator.

Use undo sbfd destination ipv6 to cancel the association between the destination IPv6 address of the detected path and the remote discriminator of the SBFD session for the initiator.

Syntax

sbfd destination ipv6 destination-ipv6-address remote-discriminator { ipv4-address | integer-value }

undo sbfd destination ipv6 destination-ipv6-address

Default

The destination IPv6 address of the detected path is not associated with the remote discriminator of the SBFD session for the initiator.

Views

System view

Predefined user roles

network-admin

Parameters

destination-ipv6-address: Specifies a valid global unicast IPv6 address as the destination IPv6 address of the detected path.

ipv4-address: Specifies a valid unicast IPv4 address as the remote discriminator.

integer-value: Specifies an integer as the remote discriminator. The value range for this argument is 1 to 4294967295.

Usage guidelines

This command allows you to use the specified remote discriminator for an SBFD session to detect an SRv6 TE policy.

The initiator selects a remote discriminator for an SBFD session as follows:

1.     Selects the remote discriminator of the SBFD session used for SRv6 TE policy connectivity detection.

2.     Selects the remote discriminator specified in this command.

If you do not specify the remote discriminator for SBFD to detect an SRv6 TE policy, the SBFD session cannot be established.

When the peer CE is dual-homed to two PEs in public network IP over SRv6 BE, IP L3VPN over SRv6 BE, or EVPN L3VPN over SRv6 BE, the local PE generates a primary path and a backup path after you enable FRR on it. To quickly detect failures and forward traffic through the backup path when the primary path fails, you can configure SBFD to detect the SRv6 locator route advertised through BGP by the peer PE. For this function to take effect, perform the following tasks:

·     Execute the sbfd destination ipv6 remote-discriminator command on the local PE to specify the remote discriminator for an SBFD session to detect the SRv6 locator.

·     Execute the sbfd local-discriminator command on the peer PE of the primary path to specify the local discriminator for the reflector.

·     Make sure the remote discriminator on the local PE is consistent with the local discriminator on the peer PE.

You can execute this command repeatedly to configure multiple associations between destination IPv6 addresses and remote discriminators for the initiator.

When configuring or canceling an association, the SBFD session might flap if it is in up state.

Examples

# Enable SBFD for all SRv6 TE policies, and associate destination IPv6 address 10::1 of the SRv6 TE policy with remote discriminator 1.1.1.1 of the SBFD session for the initiator.

<Sysname> system-view

[Sysname] segment-routing ipv6

[Sysname-segment-routing-ipv6] traffic-engineering

[Sysname-srv6-te] srv6-policy sbfd

[Sysname-srv6-te] quit

[Sysname-segment-routing-ipv6] quit

[Sysname] sbfd destination ipv6 10::1 remote-discriminator 1.1.1.1

Related commands

locator-sbfd enable (Segment Routing Command Reference)

sbfd (Segment Routing Command Reference)

sbfd local-discriminator

srv6-policy sbfd (Segment Routing Command Reference)

sbfd local-discriminator

Use sbfd local-discriminator to set the local discriminator for the reflector.

Use undo sbfd local-discriminator to remove the local discriminator setting for the reflector.

Syntax

sbfd local-discriminator { ipv4-address | integer-value }

undo sbfd local-discriminator { ipv4-address | integer-value }

Default

No local discriminator is set for the reflector.

Views

System view

Predefined user roles

network-admin

Parameters

ipv4-address: Specifies a valid unicast IPv4 address as the local discriminator.

integer-value: Specifies an integer as the local discriminator. The value range for this argument is 1000001 to 4294967295.

Usage guidelines

In a BFD session, both ends periodically send BFD packets to detect bidirectional forwarding path failures. SBFD is a unidirectional failure detection mechanism that provides shorter detection time than BFD. SBFD is used in scenarios where only one end of a link requires failure detection, such as MPLS TE tunnel establishment through static SRLSP.

An SBFD session involves the following roles:

·     Initiator—Periodically sends SBFD control packets to detect connectivity to remote entities. An initiator initiates SBFD sessions and maintain SBFD session state.

·     Reflector—Listens for incoming SBFD control packets on local entities and replies with response SBFD control packets.

The remote discriminator in SBFD control packets sent by the initiator must be specified in the sbfd local-discriminator command. Otherwise, the reflector does not reply with response SBFD control packets.

You can execute this command multiple times to configure multiple local discriminators.

A node can act as the initiator of one session and the reflector of another session at the same time.

Examples

# Specify 1.1.1.1 as the local discriminator for the reflector.

<Sysname> system-view

[Sysname] sbfd local-discriminator 1.1.1.1

# Specify 1000001 as the local discriminator for the reflector.

<Sysname> system-view

[Sysname] sbfd local-discriminator 1000001

Related commands

display sbfd session

mpls bfd (MPLS Command Reference)

sbfd source-ipv4

Use sbfd source-ipv4 to configure the source IPv4 address for the initiator to send SBFD packets.

Use undo sbfd source-ipv4 to restore the default.

 

 

NOTE:

This command is supported only in R5212P01 and later versions.

 

Syntax

sbfd source-ipv4 ipv4-address

undo sbfd source-ipv4

Default

No source IPv4 address is configured for the initiator to send SBFD packets.

Views

System view

Predefined user roles

network-admin

Parameters

ipv4-address: Specifies the source IPv4 address for SBFD packets. The source IPv4 address must be a valid unicast IPv4 address in dotted decimal notation and cannot be a loopback address.

Usage guidelines

To use SBFD to detect an SRv6 TE policy whose egress node is located in a pure IPv4 network, perform the following tasks:

·     Make sure the Encaps encapsulation mode is configured for the SBFD packets used to detect SRv6 TE policy connectivity.

·     Configure the source IPv4 address for the initiator to send SBFD packets.

You can configure the source IPv4 address for sending SBFD packets in one of the following ways:

·     Use the source-address ipv4 command in SRv6 TE policy view.

·     Use the sbfd source-ipv4 command in system view, and make sure the reflector has a route to the configured IPv4 address.

The device selects the source address for SBFD packets in the following order:

1.     The source address configured by using the source-address ipv4 command.

2.     The source address configured by using the sbfd source-ipv4 command.

Examples

# Configure source IPv4 address 1.1.1.1 for the initiator to send SBFD packets.

<Sysname> system-view

[Sysname] sbfd source-ipv4 1.1.1.1

Related commands

source-address ipv4 (Segment Routing Command Reference)

sbfd source-ipv6

Use sbfd source-ipv6 to specify the source IPv6 address used by the initiator to send SBFD control packets.

Use undo sbfd source-ipv6 to restore the default.

Syntax

sbfd source-ipv6 ipv6-address

undo sbfd source-ipv6

Default

No source IPv6 address is specified for SBFD control packets.

Views

System view

Predefined user roles

network-admin

Parameters

ipv6-address: Specifies a unicast IPv6 address.

Usage guidelines

To use SBFD to detect the connectivity of forwarding paths in an SRv6-TE policy or in SRv6 BE mode, you must execute this command on the initiator. In addition, a route to the specified IPv6 address must exist on the reflector.

Examples

# Specify 80::2 as the source IPv6 address for SBFD control packets.

<Sysname> system-view

[Sysname] sbfd source-ipv6 80::2

 

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