peer bfd
Function
The peer bfd command sets BFD detection parameters for a peer or peer group.
The undo peer bfd command restores default BFD detection parameter values.
By default, the interval for sending BFD packets is 1000 ms, the interval for receiving BFD packets is 1000 ms, and the local detection multiplier is 3.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this command.
Format
peer { group-name | ipv4-address } bfd { min-tx-interval min-tx-interval | min-rx-interval min-rx-interval | detect-multiplier multiplier } *
peer { group-name | ipv6-address } bfd { min-tx-interval min-tx-interval | min-rx-interval min-rx-interval | detect-multiplier multiplier | wtr wtr-value } *
undo peer { group-name | ipv4-address } bfd { min-tx-interval | min-rx-interval | detect-multiplier } *
undo peer { group-name | ipv6-address } bfd { min-tx-interval | min-rx-interval | detect-multiplier | wtr } *
undo peer { group-name | ipv4-address } bfd { min-tx-interval min-tx-interval | min-rx-interval min-rx-interval | detect-multiplier multiplier } *
undo peer { group-name | ipv6-address } bfd { min-tx-interval min-tx-interval | min-rx-interval min-rx-interval | detect-multiplier multiplier | wtr wtr-value } *
Parameters
| Parameter | Description | Value |
|---|---|---|
| group-name | Specifies the name of a peer group. | The name is a string of 1 to 47 case-sensitive characters, with spaces not supported. When double quotation marks are used around the string, spaces are allowed in the string. |
| ipv4-address | Specifies the IPv4 address of a peer. | It is in dotted decimal notation. |
| ipv6-address | Specifies the IPv6 address of a peer. | The value is a 32-digit hexadecimal number, in the format of X:X:X:X:X:X:X:X. |
| min-tx-interval min-tx-interval | Specifies the interval at which BFD packets are sent. | The value is an integer that ranges from 100 to 1000, in milliseconds.
|
| min-rx-interval min-rx-interval | Specifies the interval at which BFD packets are received. | The value is an integer that ranges from 100 to 1000, in milliseconds.
|
| detect-multiplier multiplier | Specifies the local detection time multiplier. | The value is an integer that ranges from 3 to 50. By default, the value is 3. |
| wtr wtr-value | Specifies the interval for waiting for the BFD session to restore. | The value is an integer that ranges from 1 to 60, in minutes. By default, the value is 0 minute, indicating no waiting. |
Views
BGP view, BGP-VPN instance IPv4 address family view, BGP-VPN instance IPv6 address family view
Usage Guidelines
Usage Scenario
BFD provides millisecond-level fault detection. It helps BGP to detect faults in neighboring devices or links more quickly, and instructs BGP to recalculate routes for correct packet forwarding. The peer bfd command can be used to set the values of BFD session parameters on a specified interface.
The BFD configuration of a peer takes precedence over that of the peer group to which the peer belongs. If BFD is not configured on a peer and the peer group to which the peer belongs is enabled with BFD, the peer will inherit the BFD configurations of the peer group.
Prerequisites
Peer relationships have been established using the peer as-number command.
A BFD session can be established only when the corresponding BGP session is in the Established state.
Precautions
If the peer bfd command is run multiple times, the latest configuration overwrites the previous one. The BFD session uses the latest parameters as the detection parameters.
Assume that BFD is configured on a peer group. If the peer bfd block command is not run on members of the peer group, the members will establish BFD sessions.
If BFD parameters are set on a peer, a BFD session will be established by using the BFD parameters on the peer.