David’s Cisco Networking Blog

Dec 23 2008   4:27AM GMT

How to Configure Integrated IS-IS

David Davis David Davis Profile: David Davis

Cisco Integrated IS-IS is part of a link-state Interior Gateway protocol and supports CLNP, IPv4, and IPv6.  To verify your platform support, please see my article covering the Cisco IOS Feature Navigator. An Intermediate-System-to-Intermediate System (IS) operates at Level 1 or Level 2 routing, or both.

Following is a sample configuration showing a router using IS-IS as the IP protocol.

routerB(config)# router isis
routerB(config-router)# net 49.0001.0000.0000.000a.00
routerB(config-router)# interface ethernet1/1
routerB(config-if)# ip address
routerB(config-if)# ip router isis
routerB(config-if)# interface serial 2/0
routerB(config-if)# ip router isis
routerB(config-if)# ip address

Additionally, do the show ip route command to verify your configuration. Notice the “i” routes. These are your IS-IS Routes:

RouterB# show ip route
Codes: C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route
Gateway of last resort is not set
C is directly connected, Serial5/0 is subnetted, 1 subnets
i L1 [115/20] via, Serial5/0 is subnetted, 1 subnets
i L1 [115/20] via, Serial2/0

For more information, please see the Cisco documentation on Cisco IOS IP Routing Protocols and Cisco’s Configuring IS-IS for IP on Cisco Routers.

 Comment on this Post

There was an error processing your information. Please try again later.
Thanks. We'll let you know when a new response is added.
Send me notifications when other members comment.

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Forgot Password

No problem! Submit your e-mail address below. We'll send you an e-mail containing your password.

Your password has been sent to:

Share this item with your network: