When I try to add an IP rule for IPv6 on my Linux system, it errors out:
$ ip -6 rule add fwmark 0xfab lookup 0xf RTNETLINK answers: Address family not supported by protocol
I checked out the IP rule code; it issues a netlink message to the kernel. Probably I need to load some module, but I don't know which. What do I need to do to fix this?
I am using linux 18.104.22.168 built from kernel sources
Solution: By default linux build doesn't support multiple routing tables for IPv6. You need to enable CONFIG_IPV6_MULTIPLE_TABLES for multiple IPv6 routing table support.