Configuration procedure
Configuring IS-IS FRR to calculate a backup next hop through LFA calculation
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. (Optional.) Disable LFA calculation on the interface. | isis fast-reroute lfa-backup exclude | By default, the interface participates in LFA calculation, and can be elected as a backup interface. |
4. Return to system view. | quit | N/A |
5. Enter IS-IS IPv4 unicast address family view. | isis [ process-id ] [ vpn-instance vpn-instance-name ] cost-style { wide | wide-compatible } address-family ipv4 [ unicast ] | N/A |
6. Enable IS-IS FRR to calculate a backup next hop through LFA calculation. | fast-reroute lfa | By default, IS-IS FRR is disabled. |
Configuring IS-IS FRR using a routing policy
You can use the apply fast-reroute backup-interface command to specify a backup next hop in a routing policy for routes matching specific criteria. You can also perform this task to reference the routing policy for IS-IS FRR. For more information about the apply fast-reroute backup-interface command and routing policy configurations, see "Configuring routing policies."
To configure IS-IS FRR using a routing policy:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. (Optional.) Disable LFA calculation on the interface. | isis fast-reroute lfa-backup exclude | By default, the interface participates in LFA calculation, and can be elected as a backup interface. |
4. Return to system view. | quit | N/A |
5. Enter IS-IS IPv4 unicast address family view. | isis [ process-id ] [ vpn-instance vpn-instance-name ] cost-style { wide | wide-compatible } address-family ipv4 [ unicast ] | N/A |
6. Enable IS-IS FRR using a routing policy. | fast-reroute route-policy route-policy-name | By default, this feature is not enabled. |
Enabling BFD for IS-IS FRR
By default, IS-IS FRR does not use BFD to detect primary link failures. To speed up IS-IS convergence, enable BFD for IS-IS FRR to detect primary link failures.
To enable BFD control packet mode for IS-IS FRR:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter interface view. | interface interface-type interface-number | N/A |
3. Enable BFD control packet mode for IS-IS FRR. | isis primary-path-detect bfd ctrl | By default, BFD control packet mode is disabled for IS-IS FRR. |
To enable BFD echo packet mode for IS-IS FRR:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Configure the source IP address of BFD echo packets. | bfd echo-source-ip ip-address | By default, the source IP address of BFD echo packets is not configured. The source IP address cannot be on the same network segment as any local interface's IP address. For more information, see High Availability Command Reference. |
3. Enter interface view. | interface interface-type interface-number | N/A |
4. Enable BFD echo packet mode for IS-IS FRR. | isis primary-path-detect bfd echo | By default, BFD echo packet mode is disabled for IS-IS FRR. |