Configuring Dynamic BFD for IPv4 Static Routes
Dynamic BFD for IPv4 static routes enables devices to fast detect link changes, improving network reliability.
Usage Scenario
To use BFD sessions to provide link detection for IPv4 static routes on the public network, you can bind IPv4 static routes to BFD sessions. One IPv4 static route can be bound to one BFD session.
Optimal IPv4 static routes are delivered to the forwarding table for packet forwarding. However, IPv4 static routes cannot detect the status of the link to the next hop. You can bind IPv4 static routes to BFD sessions. A BFD session can fast detect changes over a link and inform the routing management system of the changes. The routing management system immediately deletes the IPv4 static route that is bound to the BFD session from the forwarding table and recalculates another active route. In this manner, fast route convergence is implemented.
Pre-configuration Tasks
Before configuring dynamic BFD for static routes, configure parameters of the link layer protocol and IP addresses for interfaces and ensure that the link layer protocol on the interfaces is Up.
Procedure
- Run system-view
The system view is displayed.
- Run bfd
Global BFD is enabled on the node.
- Run quit
Return to the system view.
- (Optional) Run ip route-static default-bfd [ min-rx-interval min-rx-interval ] [ min-tx-interval min-tx-interval ] [ detect-multiplier multiplier ] *
Global BFD parameters are configured for IPv4 static routes.
- Run ip route-static bfd [ interface-type interface-number | vpn-instance vpn-instance-name ] nexthop-address [ local-address address ] [ min-rx-interval min-rx-interval ] [ min-tx-interval min-tx-interval ] [ detect-multiplier multiplier ] *
The BFD parameters are set for an IPv4 static route.
If interface-type interface-number is not set, local-address address must be specified.
If none of min-rx-interval, min-tx-interval, or detect-multiplier is specified, the default values of the BFD parameters are used.
- Run either of the following commands as required:
Run ip route-static ip-address { mask | mask-length } { nexthop-address | interface-type interface-number [ nexthop-address ] | vpn-instance vpn-instance-name nexthop-address } bfd enable [ description text ]
A public network IPv4 static route is bound to a BFD session.
Run ip route-static vpn-instance vpn-source-name destination-address { mask | mask-length } { nexthop-address | interface-type interface-number [ nexthop-address ] | vpn-instance vpn-instance-name nexthop-address } bfd enable [ description text ]
A VPN network IPv4 static route is bound to a BFD session.
The outbound interface and next hop IP address specified when binding the IPv4 static route to a BFD session must be the same as those specified when configuring BFD parameters for the IPv4 static route.
- Run commit
The configuration is committed.
Checking the Configurations
Run the following commands to check the previous configuration.
Run the display bfd session { all | discriminator discr-value } [ verbose ] command to check detailed BFD session information.
Run the display current-configuration | include bfd command to check configurations of BFD for static routes.
You can check the information about a BFD session only after parameters of the BFD session are set and the BFD session is established.
If a BFD session has been established, the status of the BFD session is Up. Run the display current-configuration | include bfd command in the system view, and you can view that the BFD session has been bound to a static route.