IPv6 auto config through trunk port

[feilertsen]

Hi all!

I'm working on a school assignment where I have been instructed to get an enterprise network ready for IPv6. We are working in Packet Tracer, where DHCP-relay is for some reason unavailable. As a workaround I wanted to configure hosts with IPv6 using SLAAC.

Basically hosts are connected to switch1 fa0/2 (switchport access vlan 10).

Switch1 fa0/1 (switchport mode trunk) is connected to a Layer 3 switch fa0/1 (switchport mode trunk)

On Layer 3 switch I have activated interface vlan 10 and set an IPv6 address.

I was expecting the host to be able to receive an IPv6 address through auto config with this set-up, but it fails.

So my question is this. Did I configure it wrong, or is Packet Tracer not working properly?

I was thinking there could ba problem with auto config NDP messages through the trunk port.

Thanks!

- Fred

[Harold Ritter]

Hi Fred,

Technically, this should not be an issue. Could you please provide the config for vlan 10 from the L3 switch?

Regards,

[feilertsen]

Thanks! Here is the VLAN10 configuration. (The ip helper-address is for the IPv4 dhcp server..)

interface Vlan10

mac-address 0060.2fd6.a101

ip address 172.16.0.1 255.255.248.0

ip helper-address 172.16.54.186

ipv6 address 2003:D8F:1111:10::/64 eui-64

ipv6 enable

[Harold Ritter]

Do you have "ipv6 unicast-routing" enabled in global configuration mode?

Regards,

[feilertsen]

Yes, IPv6 Unicast-Routing is enabled.

[Harold Ritter · Accepted solution]

The ND Router Advertisement should get from the router to the hosts regardless of the L2 topology then. I suspect it might be an issue/limitation with Cisco Packet Tracer.

Regards,