`ip mrule show` depends on CONFIG_IP_MROUTE_MULTIPLE_TABLES
for IPv4 and CONFIG_IPV6_MROUTE_MULTIPLE_TABLES for IPv6,
if either is missing then it fails:
% ip -6 mrule show
32767: from all lookup main
% ip -4 mrule show
RTNETLINK answers: Address family not supported by protocol
Dump terminated
% ip mrule show
RTNETLINK answers: Address family not supported by protocol
Dump terminated
% grep MROUTE /boot/config-$(uname -r)
CONFIG_IP_MROUTE=y
# CONFIG_IP_MROUTE_MULTIPLE_TABLES is not set
CONFIG_IPV6_MROUTE=y
CONFIG_IPV6_MROUTE_MULTIPLE_TABLES=y
% uname -r
4.13.13-6-pve
Noticed on a customer system running Proxmox kernel,
reported towards upstream: https://bugzilla.proxmox.com/show_bug.cgi?id=1711
exectest ip && ip link show > ip_link
exectest ip && ip maddr show > ip_maddr
exectest ip && ip mroute show > ip_mroute
- exectest ip && ip mrule show > ip_mrule
+ exectest ip && ip mrule show > ip_mrule 2>ip_mrule.error
exectest ip && ip neigh show > ip_neigh
exectest ip && ip netns list > ip_netns
exectest ip && ip ntable show > ip_ntable