H3C SOHO IE4300, Command Reference Manual

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Predefined user roles
network-admin
Parameters
vpn-instance vpn-instance-name
: Specifies an MPLS L3VPN instance by its name, a
case-sensitive string of 1 to 31 characters. If you do not specify a VPN instance, the command
enables IPv4 or IPv6 RIB inter-protocol FRR for the public network.
Usage guidelines
This command allows a device to perform fast rerouting between routes of different protocols. A
backup next hop is automatically selected to reduce the service interruption time caused by
unreachable next hops. When the next hop of the primary link fails, the traffic is redirected to the
backup next hop.
This command uses the next hop of a route from a different protocol as the backup next hop for the
faulty route, which might cause loops.
Inter-protocol FRR cannot select a backup next hop from routes in the RIB that have the same next
hop, output interface, and destination as those of the faulty route.
Examples
# Enable IPv4 RIB inter-protocol FRR for the public network.
<Sysname> system-view
[Sysname] rib
[Sysname-rib] address-family ipv4
[Sysname-rib-ipv4] inter-protocol fast-reroute
ip route fast-switchover enable
Use ip route fast-switchover enable to enable IPv4 route fast switchover.
Use undo ip route fast-switchover enable to disable IPv4 route fast switchover.
Syntax
ip route fast-switchover enable
undo ip route fast-switchover enable
Default
IPv4 route fast switchover is disabled.
Views
System view
Predefined user roles
network-admin
Usage guidelines
Use this command if a physical interface is the output interface for a large number of routes,
including primary/secondary routes. When a link failure occurs on an interface, the device typically
performs the following operations before switching the traffic to a valid route:
1. Deletes all ARP entries for the link.
2. Instructs the FIB to delete the associated FIB entries.
This process is time-consuming and interruptive if a large number of routes traverse the interface.
Route fast switchover minimizes traffic interruption by instructing the FIB to delete the affected FIB
entries immediately without having to wait for the ARP entries to be deleted.