Configuring IP FRR on the Public Network
Usage Scenario
On a traditional IP network, when a lower-layer failure occurs on the forwarding link of a device, the physical interface of the device becomes Down. After the device detects the failure, it instructs the upper-layer routing system to recalculate routes and update routing information. It often takes the routing system several seconds to reselect an available route.
Second-level convergence is intolerable to the services that are quite sensitive to delay and packet loss because it may lead to service interruption. For example, Voice over Internet Protocol (VoIP) services are only tolerant of millisecond-level interruption. IP FRR ensures that the forwarding system rapidly responds to link failures and uses backup routes to forward data, minimizing service traffic interruption.
Among the AR160 series routers, the AR169, AR169G-L, AR169CVW, AR169CVW-4B4S, AR169-P-M9, AR169W-P-M9, AR169RW-P-M9, and AR161FW-P-M5 do not support the function.
Pre-configuration Tasks
Before configuring IP FRR on the public network, complete the following tasks:
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Configuring static routes or an IGP to ensure that there are reachable IP routes between devices
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Configuring different costs for routes to generate two non-equal-cost routes
Configuration Procedure
Configure a route-policy and then enable IP FRR on the public network for the route-policy.
Procedure
- Configure a route-policy.
- Run apply backup-nexthop ip-address
The backup next hop is set.
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If a backup outbound interface is specified on a P2P link, no backup next hop needs to be specified.
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If a backup outbound interface is specified on a non-P2P link, a backup next hop needs to be specified.
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- Run apply backup-nexthop ip-address
- Enable IP FRR on the public network.
- Run ip frr route-policy route-policy-name
IP FRR on the public network is enabled.
When using IP FRR, use this command to enable IP FRR so that the route-policy can take effect.
Only one route-policy can be configured every time you use the command. If you run the command multiple times, only the latest configuration takes effect.
- Run ip frr route-policy route-policy-name
