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Figure 68
Network diagram for IS-IS FRR configuration
Switch S
Switch D
Switch A
Loop 0
1.1.1.1/32
Vla
n-i
nt1
00
12
.12
.12
.1/
24
Vlan-int200
13.13.13.1/24
Vlan-int200
13.13.13.2/24
Vla
n-i
nt1
00
12
.12
.12
.2/
24
Vla
n-in
t10
1
24.2
4.2
4.2
/24
Vla
n-in
t10
1
24.2
4.2
4.4
/24
Loop 0
4.4.4.4/32
Link A
Link B
Configuration procedure
1.
Configure IP addresses for the interfaces on each switch and configure IS-IS.
Follow
to configure the IP address and subnet mask of each interface on the switches. (Details
not shown)
Configure IS-IS on the switches, ensuring that Switch A, Switch D, and Switch S can communicate with
each other at Layer 3. (Details not shown)
2.
Configure IS-IS FRR.
You can enable IS-IS FRR to either automatically calculate a backup next hop, or to designate a backup
next hop by using a referenced routing policy.
Method I: Enable IS-IS FRR to automatically calculate a backup next hop.
# Configure Switch S.
<SwitchS> system-view
[SwitchS] bfd echo-source-ip 1.1.1.1
[SwitchS] isis 1
[SwitchS-isis-1] fast-reroute auto
[SwitchS-isis-1] quit
# Configure Switch D.
<SwitchD> system-view
[SwitchD] bfd echo-source-ip 4.4.4.4
[SwitchD] isis 1
[SwitchD-isis-1] fast-reroute auto
[SwitchD-isis-1] quit
Method II: Enable IS-IS FRR to designate a backup next hop by using a referenced routing policy.
# Configure Switch S.
<SwitchS> system-view
[SwitchS] bfd echo-source-ip 1.1.1.1
[SwitchS] ip ip-prefix abc index 10 permit 4.4.4.4 32
[SwitchS] route-policy frr permit node 10
[SwitchS-route-policy] if-match ip-prefix abc
[SwitchS-route-policy] apply fast-reroute backup-interface vlan-interface 100
backup-nexthop 12.12.12.2
[SwitchS-route-policy] quit
[SwitchS] isis 1
[SwitchS-isis-1] fast-reroute route-policy frr
[SwitchS-isis-1] quit