I wonder if there is one use case one can think of that is not possible with Cisco IOS:
Establish a IPsec tunnel over an IPv6 network tranporting both IPv4 and Ipv6 traffic. Even IPsec tunnel over an IPv6 network transporting IPv4 only does not work.
I tried several things in my lab but couldn't get it running.
I tried to search the net for my use case but I only find the other way round.
Question: is it possible to achieve connectivity of the following IPv4 addresses over an IIPsec tunnel over Ipv6 network?
Ultimately, the same tunnel should be capable transporting both. A dedicated Tunnel for IPv4 and IPv6 tunnel on the same routers would also be OK.
Svr A ( ) Svr B
+----+ , `,( .) +----+
| | +----+ ( .( ...) +----+ | |
| |---| R1 |---` .....)---| R2 |---| |
| | +----+ ( ......) +----+ | |
10.0.23.1/24 IPv6 only 10.0.42.1/24