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Configuring static route frr, Configuration prerequisites, Configuration procedure – H3C Technologies H3C SR8800 User Manual

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12

Step Command

Remarks

3.

Enable BFD echo
packet mode for

static routes.

Approach 1:
ip route-static dest-address { mask | mask-length }

interface-type

interface-number next-hop-address bfd

echo-packet [ preference preference-value ] [ tag tag-value ]
[ description description-text ]

Approach 2:

ip route-static vpn-instance s-vpn-instance-name&<1-6>
dest-address { mask | mask-length } interface-type

interface-number next-hop-address bfd echo-packet

[ preference preference-value ] [ tag tag-value ] [ description
description-text

]

Use either
approach.

NOTE:

If route flaps occur, enabling BFD could worsen them.

For the echo mode, only one end needs to establish the BFD session, and the source address of echo
packets must be configured.

BFD cannot be used for a static route with the outbound interface having the spoofing attribute.

BFD can be used for static routes with direct next hops rather than indirect next hops.

A BFD session is established at only one end when the echo mode is used.

The BFD echo packet mode is not supported on tunnel interfaces at present.

For how to configure static routing, see the chapter “Configuring static routing.”

Configuring static route FRR

When a link or a router fails, the packets on the path may be discarded, or a routing loop occurs. To

avoid such problems, you can enable static route fast reroute (FRR).

Figure 1 Network diagram

As shown in

Figure 1

, upon a link failure, FRR designates a backup next hop by using a routing policy for

routes matching the specified criteria. Packets are directed to the backup next hop to avoid traffic

interruption.

Configuration prerequisites

Create a routing policy to be referenced by FRR and use the apply fast-reroute backup-interface

command to specify a backup next hop in the routing policy. For more information about the command
and routing policy configurations, see the chapter “Configuring routing policies.”

Configuration procedure

To configure static route FRR: