IPv6 ND - Default route not installed

[oscarjramirez]

Hi,

I'm trying to install a default IPv6 route through RA ND on a serial link. This is my configuration:

R4#

ipv6 unicast-routing

!

!

interface Serial0/1

description Connected to R5

ipv6 address 2001:4444::/64 eui-64

ipv6 nd prefix 2001:4444::/64 infinite infinite

no ipv6 nd ra suppress

!

end

R5#

no ipv6 unicast-routing

!

interface Serial0/1

description Connected to R4

ipv6 address autoconfig

!

The result with this configuration is:

R5#sh ipv6 int s0/1

Serial0/1 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::20D:BCFF:FE26:7F70

  No Virtual link-local address(es):

  Description: Connected to R4

  Global unicast address(es):

    2001:4444::20D:BCFF:FE26:7F70, subnet is 2001:4444::/64 [EUI/CAL/PRE]

  Joined group address(es):

    FF02::1

    FF02::1:FF26:7F70

  MTU is 1500 bytes

  ICMP error messages limited to one every 100 milliseconds

  ICMP redirects are enabled

  ICMP unreachables are sent

  ND DAD is enabled, number of DAD attempts: 1

  ND reachable time is 30000 milliseconds

  Default router is FE80::211:5CFF:FEBA:4260 on Serial0/1

R5#

R5#sh ipv6 route

IPv6 Routing Table - 3 entries

C   2001:4444::/64 [0/0]

     via ::, Serial0/1

L   2001:4444::20D:BCFF:FE26:7F70/128 [0/0]

     via ::, Serial0/1

L   FF00::/8 [0/0]

     via ::, Null0

R5#

So far so good, but I tried with another link between FastEthernet interfaces on Catalyst 3560 switches:

SW4#sh ipv6 int f0/20

FastEthernet0/20 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::223:34FF:FE20:E8C2

  No Virtual link-local address(es):

  Description: to SW3 F0/20

  Stateless address autoconfig enabled

  Global unicast address(es):

    2001:44::223:34FF:FE20:E8C2, subnet is 2001:44::/64 [EUI/CAL/PRE]

  Joined group address(es):

    FF02::1

    FF02::1:FF20:E8C2

  MTU is 1500 bytes

  ICMP error messages limited to one every 100 milliseconds

  ICMP redirects are enabled

  ICMP unreachables are sent

  ND DAD is enabled, number of DAD attempts: 1

  ND reachable time is 30000 milliseconds (using 24342)

  Default router is FE80::AEA0:16FF:FEAC:C6C2 on FastEthernet0/20

SW4#

SW4#sh ipv6 route

IPv6 Routing Table - Default - 4 entries

S   ::/0 [1/0]

     via FE80::AEA0:16FF:FEAC:C6C2, FastEthernet0/20

C   2001:44::/64 [0/0]

     via FastEthernet0/20, directly connected

L   2001:44::223:34FF:FE20:E8C2/128 [0/0]

     via FastEthernet0/20, receive

L   FF00::/8 [0/0]

     via Null0, receive

SW4#

So, my question is, what I need to get installed the default route in the serial link scenario?

Thanks in advance!!!

Regards,

Oscar Ramirez.

[cadet alain]

Hi,

just by doing this: ipv6 unicast-routing

Regards.

Alain.

[oscarjramirez]

Thanks Cadet, but I already tried it. It must be applied only on the server router, the client must not have it.

[cadet alain]

Hi Oscar,

If your router is an IPv6 host then how can he have a default route in its routing table?

try again and shut/no shut the interface.

if it doesn't work I'll lab it up.

Regards.

Alain.

[oscarjramirez]

Hi Alain,

Indeed I put the two scenarios. In the 3560s link, the server device sends RA with the prefix (it has ipv6 unicast-routing configured) and the client (ipv6 unicast-routing disabled) puts the default "::" on its routing table.

In the 3725 serial link, it doesn´t result. I don't know what can be happening.

Regards,

Oscar.

[oscarjramirez]

In fact, this should be the behavior for the serial link:

06:08:25: ICMPv6-ND: Selected new default router FE80::AEA0:16FF:FEAC:C6C2 on FastEthernet0/20

06:08:25: ICMPv6-ND: Installed default to FE80::AEA0:16FF:FEAC:C6C2 on FastEthernet0/20

Thanks,

Oscar.

[cadet alain]

Hi Oscar,

thanks for the info.

Regards.

Alain.

[oscarjramirez]

It's an IOS matter. I tried with 12.4(24)T and it works fine. Thanks a lot.