Purpose
Command or Action
RP/0/RP0/CPU0:router(config-isis)# address-family
ipv4 unicast
Configures a router to generate and accept only wide-link
metrics in the Level 1 area.
metric-style wide
[
transition
] [
level
{
1
|
2
}]
Example:
Step 4
RP/0/RP0/CPU0:router(config-isis-af)# metric-style
wide level 1
Installs all routes tagged with the value 3 first.
spf prefix-priority
[
level
{
1
|
2
}] {
critical
|
high
|
medium
} {
access-list-name
|
tag tag
}
Step 5
Example:
RP/0/RP0/CPU0:router(config-isis-af)# spf
prefix-priority high tag 3
commit
Step 6
Configuring IP Fast Reroute Loop-free Alternate
This optional task describes how to enable the IP fast reroute (IPFRR) loop-free alternate (LFA) computation
to converge traffic flows around link failures.
To enable node protection on broadcast links, IPFRR and bidirectional forwarding detection (BFD) must be
enabled on the interface under IS-IS.
Note
Before you begin
IPFRR is supported on the Cisco IOS XR. IPv4 address families and single-level interfaces are supported.
Multiprotocol Label Switching (MPLS) FRR and IPFRR cannot be configured on the same interface
simultaneously.
Note
SUMMARY STEPS
1.
configure
2.
router isis instance-id
3.
interface type interface-path-id
4.
circuit-type
{
level-1
|
level-1-2
|
level-2-only
}
5.
address-family ipv4 unicast
6.
ipfrr lfa
{
level
{
1
|
2
}}
7.
ipfrr lfa exclude interface type interface-path-id
8.
commit
Routing Configuration Guide for Cisco NCS 6000 Series Routers, IOS XR Release 6.4.x
237
Implementing IS-IS
Configuring IP Fast Reroute Loop-free Alternate