Hi,
I am facing a problem in ISIS multi topology at L1 router.
simple setup: R1-(R2-R4). IOS 12.2(33)SRE6
R2 and R4 are in same area. R4 is L1 only router and R2-R4 is L1.
ipv4 is working fine, R4 can install a single L1 ipv4 default route with R2 as exit point.
When ipv6 is configured, R4 can install L1 ipv6 default route ONLY when R4 is NOT configured as "multi topology" under ipv6 address-family.
If R4 is configured with "multi-topology" under ipv6 address-family, it can't install the ipv6 default route!
It does not matter whether R2 is configured "multi-topology" or not. It wouldn't affect the result.
Does anyone know the reason please? Thanks
=========================================================================
R2 config:
interface Loopback0
ip address 2.2.2.2 255.255.255.255
ipv6 address 2001::2/128
isis circuit-type level-2-only
interface GigabitEthernet2/0
ip address 10.2.4.2 255.255.255.0
ip router isis 1
negotiation auto
ipv6 address 2001:2:4::2/64
ipv6 router isis 1
isis circuit-type level-1
isis priority 100
!
router isis 1
net 00.0002.0000.0000.0002.00
metric-style wide
passive-interface Loopback0
!
address-family ipv6
multi-topology
exit-address-family
!
R2#sh isis nei
System Id Type Interface IP Address State Holdtime Circuit Id
R4 L1 Gi2/0 10.2.4.4 UP 25 R2.01
R2#
==================================================
R4 cofig:
R4# sh ip route isis
Codes: L - local, 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, H - NHRP
+ - replicated route, % - next hop override
Gateway of last resort is 10.2.4.2 to network 0.0.0.0
i*L1 0.0.0.0/0 [115/10] via 10.2.4.2, 00:20:51, GigabitEthernet1/0
R4#
R4#
R4#sh ipv6 route isis
IPv6 Routing Table - default - 4 entries
Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
B - BGP, R - RIP, I1 - ISIS L1, I2 - ISIS L2
IA - ISIS interarea, IS - ISIS summary, D - EIGRP, EX - EIGRP external
ND - Neighbor Discovery
O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
R4# <<<<<<<<<<< none of IPv6 route received!
R4#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R4(config)#router isis 1
R4(config-router)#address-family ipv6
R4(config-router-af)#no multi-topology
R4(config-router-af)#^Z
R4#sh run
Building configuration...
<skip>
interface GigabitEthernet1/0
ip address 10.2.4.4 255.255.255.0
ip router isis 1
negotiation auto
ipv6 address 2001:2:4::4/64
ipv6 router isis 1
isis ipv6 metric 200
!
router isis 1
net 00.0002.0000.0000.0004.00
is-type level-1
metric-style wide
passive-interface Loopback0
!
!
R4#sh ipv6 route isis
IPv6 Routing Table - default - 5 entries
Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
B - BGP, R - RIP, I1 - ISIS L1, I2 - ISIS L2
IA - ISIS interarea, IS - ISIS summary, D - EIGRP, EX - EIGRP external
ND - Neighbor Discovery
O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
I1 ::/0 [115/10]
via FE80::C801:4FF:FE0C:38, GigabitEthernet1/0
R4#sh clns is-neighbors detail
System Id Interface State Type Priority Circuit Id Format
R2 Gi1/0 Up L1 100 R2.01 Phase V
Area Address(es): 00.0002
IP Address(es): 10.2.4.2*
IPv6 Address(es): FE80::C801:4FF:FE0C:38
Uptime: 00:21:46
NSF capable
Topology: IPv4, IPv6
Interface name: GigabitEthernet1/0
R4#