If L2TP hot backup is configured on LACs that work in load balancing mode, advertisement of L2TP hot backup routes can be controlled.
Context
LACs use loopback interfaces to establish L2TP tunnels with an LNS. After loopback interfaces are configured for LACs that work in load balancing mode, route advertisement can be controlled as follows:
- Configure a routing policy, in which the route to the loopback IP address of the master LAC has a smaller cost than the route to the loopback IP address of the backup LAC. In this way, the route to the master LAC is preferentially selected. For information about how to configure a routing policy, see Routing Policy Configuration in HUAWEI NetEngine 8000 F Series Router Configuration Guide - IP Routing.
- This control mode is complex to configure. If a fault occurs and then is rectified on the master LAC, the route to the master LAC cannot be automatically advertised, affecting service reliability. Configure a routing protocol to trust the costs of the imported routes to loopback IP addresses of the LACs.
Procedure
- Run system-view
The system view is displayed.
- Run peer-backup route-cost auto-advertising
The LAC is enabled to control route preference by using the default cost of the route.
- Run commit
The configuration is committed.
Follow-up Procedure
To allow the route to the loopback IP address of the master LAC to be preferentially selected, perform one of the following operations based on the used routing protocol:
For IS-IS:
Run the import-route unr route-policy route-policy-name command.
For OSPF:
Run the import-route unr route-policy route-policy-name command.
For BGP:
Run the import-route unr route-policy route-policy-name command.
To allow a routing protocol to trust the costs of imported routes to loopback IP addresses, perform one of the following operations based on the used routing protocol:
- If IS-IS is used to import direct routes, run the import-route direct inherit-cost command in the IS-IS view.
- If OSPF is used to import direct routes, run the following commands in the OSPF view:
- default cost inherit-metric
- import-route direct
- If the network command is used to import routes into the OSPF routing table, run the ospf cost inherit command in the view of the loopback interface view.
- If BGP is used to import direct routes, run the import-route direct command in the BGP view.
(Optional) Run the l2tp-tunnel_source loopback loopback-num command to configure a source L2TP tunnel interface in the RBS view so that the source interface route bound to the RBS is updated based on the link status on the network side.