176
TableID: 0x2 OrigAs: 0
NBRID: 0x26000002 LastAs: 0
AttrID: 0xffffffff Neighbor: 0.0.0.0
Flags: 0x1008c OrigNextHop: 10.1.1.100
Label: NULL RealNextHop: 10.1.1.100
BkLabel: NULL BkNextHop: N/A
Tunnel ID: Invalid Interface: GigabitEthernet2/0
BkTunnel ID: Invalid BkInterface: N/A
The output shows that Router A and Router B communicate through GigabitEthernet 2/0.
IS-IS FRR configuration example
Network requirements
As shown in
Figure 46
,Router S, Router A, and Router D reside in the same IS-IS routing domain. Run
IS-IS on all the routers to interconnect them with each other. Configure IS-IS FRR so that when Link A fails,
traffic can be switched to Link B immediately.
Figure 46
Network diagram
Configuration procedure
1.
Configure IP addresses and subnet masks for interfaces on the routers. (Details not shown.)
2.
Configure IS-IS on the routers to make sure Router A, Router D, and Router S can communicate with
each other at the network layer. (Details not shown.)
3.
Configure IS-IS FRR:
Enable IS-IS FRR to automatically calculate a backup next hop, or designate a backup next hop by
using a routing policy.
{
(Method 1.) Enable IS-IS FRR to automatically calculate a backup next hop:
# Configure Router S.
<RouterS> system-view
[RouterS] isis 1
[RouterS-isis-1] address-family ipv4
[RouterS-isis-1-ipv4] fast-reroute auto
[RouterS-isis-1-ipv4] quit
[RouterS-isis-1] quit
# Configure Router D.
<RouterD> system-view
[RouterD] isis 1
[RouterD-isis-1] address-family ipv4