The isis bfd command configures BFD session parameters.
The undo isis bfd command restores the default values.
By default, the minimum interval at which BFD packets are received and the minimum interval at which BFD packets are sent are 10 ms, and the local detection multiple is 3.
| Parameter | Description | Value |
|---|---|---|
| min-tx-interval transmit-interval |
Specifies the minimum interval at which BFD packets are sent to the peer end. |
The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10. |
| min-rx-interval receive-interval |
Specifies the minimum interval at which BFD packets are received from the peer end. |
The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10. |
| detect-multiplier multiplier-value |
Specifies a local detection multiplier. |
The value ranges from 3 to 50. |
| frr-binding |
Binds the status of the BFD session to IS-IS Auto FRR. When BFD detects a link fault on the interface, the BFD session goes Down, triggering FRR on the interface. Then, traffic is switched from the faulty link to the backup link. |
- |
| tos-exp tosexp-value |
Sets a priority for all IS-IS BFD packets of the current interface. |
The value is an integer ranging from 0 to 7. |
100GE interface view, 10GE interface view, 25GE sub-interface view, 25GE interface view, 400GE interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE electrical interface view, Global VE sub-interface view, Tunnel interface view, VBDIF interface view, VE sub-interface view, VE interface view, VLANIF interface view
Usage Scenario
BFD can provide millisecond-level fault detection, help IS-IS to detect the faults that occur on neighboring devices or links more quickly, and instruct IS-IS to recalculate routes for correct packet forwarding. The isis bfd command can be used to set values for BFD session parameters on an interface.
Prerequisites
BFD has been enabled globally, and the isis bfd enable command has been run on the interface.
Configuration Impact
The minimum interval at which BFD packets are received is obtained after the receive-interval value and the remote transmit-interval value are compared. If the local end does not receive any BFD packet from its neighbor within the period (minimum interval at which BFD packets are received x multiplier-value), the local end declares the neighbor Down.
Precautions
The priority of BFD configured on an interface is higher than that of BFD configured in a process. If BFD is enabled on an interface, BFD sessions are established with the BFD parameters set on the interface.
The set BFD session parameters take effect only when BFD is enabled on the interface.