説明
Start to troubleshoot this by pinging the loopback IPv6 address of DSW2 (2026::102:1). This can be pinged from DSW1, and R4, but not R3 or any other devices past that point. If we look at the diagram, we see that R4 is redistributing the OSPF and RIP IPV6 routes. However, looking at the routing table we see that R4 has the
2026::102 network in the routing table known via RIP, but that R3 does not have the route:
Screen Shot 2015-03-11 at 4Screen Shot 2015-03-11 at 4


When we look more closely at the configuration of R4, we see that it is redistributing OSPF routes into RIP for IPv6, but the RIP routes are not being redistributed into OSPF. That is why R3 sees R4 as an IPV6 OSPF neighbor, but does not get the 2026::102 network installed.
Screen Shot 2015-03-11 at 4

So, problem is with route redistribution on R4.