I am configuring IPv6 between a Juniper MX80 and Cisco 7206VXR which already happily run IPv4 over ISIS and iBGP.
ISIS is carrying IPv6 routes between the two devices but I have what I believe is a problem. If we imagine a network like the following;
A 3rd Router -- MX80 -- 7206
ISIS is of course only carrying loop back addresses and core interface addresses, the rest is in iBGP. Now on my 7206 I look at the route to the loopback interface of a random 3rd router attached to the other side of the MX80;
7206#show ipv6 route 2a01:xxx::yyy:yyy:yyy:133
Routing entry for 2A01:xxx::yyy:yyy:yyy:133/128
Known via "isis", distance 115, metric 10, type level-2
Route count is 1/1, share count 0
Routing paths:
FE80::5E5E:AB00:300:D1C0, GigabitEthernet0/2
Last updated 3w1d ago
My problem here is that it lists the next hop as the link-local address and not the configured public routable address.
Is this a native behavior of ISIS here or have I missed a configuration command somewhere?
7206#show run int gi0/2
Building configuration...
Current configuration : 336 bytes
!
interface GigabitEthernet0/2
mtu 1540
ip address xxxx
ip router isis
media-type rj45
speed auto
duplex auto
negotiation auto
ipv6 address 2A01:xxx:xxx:xxx:yyy:yyy:yyy:yyy/64
ipv6 nd ra suppress
ipv6 router isis
mpls ip
isis metric 10
isis ipv6 metric 10
end
mx80# show interfaces ae0.3
description "xxxx";
vlan-id 3;
family inet {
address x.x.x.x/30;
}
family iso;
family inet6 {
address 2A01:xxx:xxx:xxx:yyy:yyy:yyy:yyy/64;
}
family mpls;
Looking on the 7206 ISIS sees the MX80 as that Link-Local address for it's IPv6 address, which ties in with the above output, but why? ;
7206#show isis neighbors detail
System Id Type Interface IP Address State Holdtime Circuit Id
mx80 L2 Gi0/2 89.21.224.1 UP 7 mx80.03
Area Address(es): 49.1234.5678
SNPA: 5c5e.ab00.d1c0
IPv6 Address(es): FE80::5E5E:AB00:300:D1C0
State Changed: 3w1d
LAN Priority: 64
Format: Phase V
Remote TID: 0, 2
Local TID: 0, 2
Interface name: GigabitEthernet0/2