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IOS XR Fryguy

Time for some IS-IS routing! Between IS-IS and OSPF, those are the two most coming SP core routing protocols.

RP/0/7/CPU0:R1#conf t
Thu Mar 29 22:09:12.786 UTC

First we need to name our process
RP/0/7/CPU0:R1(config)#router isis LAB

Then configure our Network Entity ( Area )
RP/0/7/CPU0:R1(config-isis)#net 49.0000.0000.0001.00

Then we assign the interfaces to the process, as well as the address family.
RP/0/7/CPU0:R1(config-isis)#int l0
RP/0/7/CPU0:R1(config-isis-if)#address-family ipv4
RP/0/7/CPU0:R1(config-isis-if)#address-family ipv6
RP/0/7/CPU0:R1(config-isis-if-af)# exit
RP/0/7/CPU0:R1(config-isis-if)#int g0/3/0/2
RP/0/7/CPU0:R1(config-isis-if)#address-family ipv4
RP/0/7/CPU0:R1(config-isis-if-af)# exit
RP/0/7/CPU0:R1(config-isis-if)#address-family ipv6
RP/0/7/CPU0:R1(config-isis-if-af)# exit

Notice I did not specify an IS-IS Level when I started, but we can set this to Level-2
RP/0/7/CPU0:R1(config-isis)#is-type level-2-only

Now, when we show the config, you will notice Level-2 is set to the top of the config when applied, not in the order I entered it. This is the beauty of a staging config, you can enter some things in the wrong order but they will be applied in the correct order.

RP/0/7/CPU0:R1(config-isis)#sh config
Thu Mar 29 22:10:22.326 UTC
Building configuration…
!! IOS XR Configuration 4.1.1
router isis LAB
is-type level-2-only
net 49.0000.0000.0001.00
interface Loopback0
address-family ipv4 unicast
address-family ipv6 unicast
interface GigabitEthernet0/3/0/2
address-family ipv4 unicast
address-family ipv6 unicast

Now, let us commit our changes.

Time to check our IS-IS adjancies.
RP/0/7/CPU0:R1#sh isis adjacency
Thu Mar 29 22:16:21.989 UTC

IS-IS LAB Level-2 adjacencies:
System Id Interface SNPA State Hold Changed NSF IPv4 IPv6
GSR-R2 Gi0/3/0/2 00d0.7901.3a78 Up 9 00:05:52 Yes None None

Total adjacency count: 1

We can see we are adjacent with R2 via IPv4 and IPv6. Lets look at the IPv4 IS-IS routing table and then PING the loopback of R2:
RP/0/7/CPU0:R1#sh route ipv4 isis
Thu Mar 29 22:17:15.545 UTC

i L2 [115/20] via, 00:06:36, GigabitEthernet0/3/0/2

Now we can test PING:
RP/0/7/CPU0:R1#ping so l0
Thu Mar 29 22:17:37.226 UTC
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms

Ok, that worked – now we can do the same for IPv6. First we should look at the IPv6 IS-IS routes and then ping the loopback of R2.

RP/0/7/CPU0:R1#sh route ipv6 isis
Thu Mar 29 22:17:43.918 UTC

i L2 2001::2/128
[115/20] via fe80::2d0:79ff:fe01:3a78, 00:07:05, GigabitEthernet0/3/0/2

Good, we have a route. Time to a PING test!
RP/0/7/CPU0:R1#ping 2001::2 so 2001::1
Thu Mar 29 22:17:49.763 UTC
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001::2, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 3/9/34 ms

Compare that to IOS ISIS config:
Configure the process and set the level and NET
R1(config)#router isis
R1(config-router)#net 49.0000.0000.0001.00
is-type level-2

Then change context to the G0/1 interface and enable ISIS for IPv4 and IPv6
R1(config-router)#int g0/1
R1(config-if)#ip router isis
ipv6 router isis

Then change context to the Loop0 interface and enable ISIS for IPv4 and IPv6
R1(config-if)#int l0
R1(config-if)#ip router isis
R1(config-if)#ipv6 router isis

Few more steps, and configuring things under the process make much more sense than under an interface.

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