Sample IS-IS Configuration in Cisco IOS-XR, IOS and Nexus OS

 

Fig.1

 

IOS-XR

Configure Loopback

 interface Loopback0
 ipv4 address 172.16.2.1 255.255.255.255
 ipv6 address fdfe:abcd:ef12:0:172:16:2:1/128
 ipv6 enable
 

Configure P2P IP 

interface Gi0/0/0/0
 description Connection to IOS Fa0/0
 ipv4 address 172.17.0.1 255.255.255.252
 ipv4 verify unicast source reachable-via any
 ipv4 unreachables disable
 ipv6 nd suppress-ra
 ipv6 verify unicast source reachable-via any
 ipv6 address fdfe:ab12:cd34:a00:1::/127
 ipv6 enable
 ipv6 unreachables disable
 load-interval 30
 dampening

interface Gi0/0/0/1
 description Connection to NX-OS E1/1
 ipv4 address 172.18.0.1 255.255.255.252
 ipv4 verify unicast source reachable-via any
 ipv4 unreachables disable
 ipv6 nd suppress-ra
 ipv6 verify unicast source reachable-via any
 ipv6 address fdfe:ab12:cd34:a00:2::/127
 ipv6 enable
 ipv6 unreachables disable
 load-interval 30
 dampening

Configure IS-IS

router isis ABC
 is-type level-2-only
 net 49.0000.1720.1600.2001.00
 nsf ietf
 log adjacency changes
 address-family ipv4 unicast
  metric-style wide
  maximum-paths 8
 address-family ipv6 unicast
  metric-style wide
  maximum-paths 8
 

 interface Loopback0
  passive
  address-family ipv4 unicast
  address-family ipv6 unicast
 

 interface Gi0/0/0/0
  point-to-point
  address-family ipv4 unicast
  address-family ipv6 unicast

 interface Gi0/0/0/1
  point-to-point
  address-family ipv4 unicast
  address-family ipv6 unicast

IOS

Configure Loopback

interface Loopback0
 ip address 172.16.2.2 255.255.255.255
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ipv6 address fdfe:abcd:ef12:0:172:16:2:2/128
 ipv6 enable
 no ipv6 redirects

 Configure P2P IP

interface Fa0/0
 description Connection to IOS-XR Gi0/0/0/0
 dampening
 ip address 172.17.0.2 255.255.255.252
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip router isis ABC
 load-interval 30
 ipv6 address fdfe:ab12:cd34:a00:1::1/127
 ipv6 enable
 ipv6 nd ra suppress
 no ipv6 redirects
 ipv6 router isis ABC

 Configure IS-IS

router isis ABC
 net 49.0000.1720.1600.2002.00
 metric-style wide
 set-overload-bit on-startup 20
 log-adjacency-changes
 nsf ietf
 passive-interface default
 no passive-interface Fa0/0

address-family ipv6
  multi-topology
 exit-address-family

NX-OS

Configure P2P IP

interface Eth1/1
  description Connection to IOS-XR Gi0/0/0/1
  no cdp enable
  no ip redirects
  ip address 172.18.0.2/30
  ip verify unicast source reachable-via any rx
  ipv6 address fdfe:ab12:cd34:a00:2::1/127
  ipv6 verify unicast source reachable-via rx
  no ipv6 redirects
  ip router isis ABC
  ipv6 router isis ABC
  isis network point-to-point
  no isis passive-interface level-2
  no shutdown

router isis ABC
  net 49.0000.1720.1600.2003.00
  is-type level-2
  metric-style transition
  set-overload-bit on-startup 20
  log-adjacency-changes
  address-family ipv4 unicast
  address-family ipv6 unicast
    multi-topology transition
  passive-interface default level-2

VERIFICATION

IOS-XR:

RP/0/RP0/CPU0:IOS-XR#show isis adjacency | i IOS
Wed Dec 23 14:22:14.273 SST
IOS           Gi0/0/0/0       *PtoP*        Up    27   1y07w    Yes Up   Up
NX-OS     Gi0/0/0/1       *PtoP*        Up    27   1y06w    Yes Up   Up

IOS:
IOS#show isis neighbors

Tag ABC:
System Id       Type Interface     IP Address      State Holdtime Circuit Id
IOS-XR        L2   Te0/3/0         172.17.0.2          UP    28       00

NX-OS:

NX-OS# show isis adjacency
IS-IS process: ABC VRF: default
IS-IS adjacency database:
Legend: '!': No AF level connectivity in given topology
System ID       SNPA            Level  State  Hold Time  Interface
IOS-XR        N/A             2      UP     00:00:22   Ethernet1/1