Description

This article provides the basic configuration for using OSPF between a Juniper router and a Cisco router. This does not include redistribution of routes into or out of OSPF; this is for basic configuration for adjacency establishment.

Symptoms

How do I configure OSPF between a Juniper device running Junos and a Cisco router?

Solution

To configure OSPF between a Junos device and a Cisco router, the configurations below provides the base needed to establish adjacency. 

Note:  These sample configurations were done between a Juniper m10i router running Junos 9.5r1, and a Cisco 7200 running IOS 12.2.

Juniper Config :

user@juniper# show interfaces
ge-0/0/0 {
unit 0 {
family inet {
address 1.1.1.1/30;
}
}
}
lo0 {
unit 0 {
family inet {
address 5.5.5.5/32;
}
}
}
user@juniper# show protocols
ospf {
area 0.0.0.0 {
interface ge-0/0/0;
}
}
}


Cisco Config :
version 12.2

!
interface GigabitEthernet4/0
ip address 1.1.1.2 255.255.255.252
ip flow ingress
ip flow egress
ip ospf network
!
router ospf 2222
router-id 6.6.6.6
log-adjacency-changes
network 0.0.0.0 255.255.255.255 area 0
!
end

This configuration example will provide peering between the Juniper router on ge-0/0/0 and the Cisco router on GigabitEthernet4/0, with the Juniper using router ID of 5.5.5.5 and the Cisco using router ID of 6.6.6.6:
user@juniper> show ospf neighbor
Address Interface
State
ID Pri Dead
1.1.1.2
ge-0/0/0
Full
6.6.6.6 1 38