No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search


To have a better experience, please upgrade your IE browser.


CLI-based Configuration Guide - Reliability

AR100-S, AR110-S, AR120-S, AR150-S, AR160-S, AR200-S, AR1200-S, AR2200-S, and AR3200-S V200R009

Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Configuring Association Between the BFD Session Status and the Sub-interface Status

Configuring Association Between the BFD Session Status and the Sub-interface Status

Pre-configuration Tasks

Before associating the BFD session status with the sub-interface status, complete the following task:

  • Connect interfaces properly.

Configuration Process

Figure 6-20  Association between the BFD session status and the interface status


  1. Run system-view

    The system view is displayed.

  2. Run bfd

    BFD is enabled globally and the BFD view is displayed.

  3. Run default-ip-address ip-address

    The default multicast IP address for BFD is configured.

    By default, BFD uses the multicast IP address


    If multiple BFD sessions exist on a path, for example, Layer 3 interfaces are connected through Layer 2 switching devices that support BFD, configure different default multicast IP addresses for the devices where different BFD sessions are established. In this manner, BFD packets can be correctly forwarded.

  4. Run quit

    Return to the system view.

  5. Run bfd cfg-name bind peer-ip default-ip interface interface-type interface-number [ source-ip source-ip ]

    A BFD session is created.

  6. Run discriminator local discr-value

    The local discriminator is set.

  7. Run discriminator remote discr-value

    The remote discriminator is set.

    • The local discriminator of the local system must be the same as the remote discriminator of the remote system; the remote discriminator of the local system must be the same as the local discriminator of the remote system. Otherwise, BFD sessions cannot be established. After the local discriminator and the remote discriminator are configured, you cannot modify them.
    • If a BFD session is bound to the default multicast address, the local discriminator and the remote discriminator must be different.

  8. Run process-interface-status sub-if

    Association between the BFD session status with the sub-interface status is configured.

  9. Run commit

    The configuration is committed.

    When the BFD session becomes Down, the status of the main interface bound to the BFD session and its sub-interface also becomes Down.

    • The BFD session does not report the BFD status to the bound interface immediately after the commit command is executed because the BFD session may not be set up or not Up. This prevents the BFD session from reporting an incorrect state to the interface. When the BFD status changes, the BFD session reports the BFD status to the interface to trigger the interface status change.

    • If the BFD session must be synchronized to an interface immediately, ensure that the BFD configurations on the two ends are the same and run the shutdown and undo shutdown commands on the BFD session. When the undo shutdown command is executed for a BFD session, a BFD session detection timer is started. If the BFD session becomes Up through negotiation before the timer times out, the BFD session notifies an interface of the Up state. Otherwise, the BFD session considers the link faulty and notifies the interface of the Down state. The status of a BFD session and the status of an interface can be synchronized in real time.

    • If the process-interface-status command is saved in the configuration file, the BFD session for which the process-interface-status command is run notifies an interface that the BFD session becomes Down when the device is restarted. This is because the initial status of the interface is Down.

    • Before the BFD session status is associated with the interface status, the BFD configurations on two ends must be correct and matched. If the BFD status on the local interface is Down, check whether the BFD configuration on the remote end is correct and the BFD session is shut down.

Updated: 2019-05-17

Document ID: EDOC1000174116

Views: 53867

Downloads: 19

Average rating:
This Document Applies to these Products
Related Version
Related Documents
Previous Next