While playing with linux bridging and ipv6 on ubuntu focal, I met an issue that I would like to understand.
When I manually set the bridge mac address, bridge ipv6 address is not working anymore, why ?
Bridge with system allocated mac address [Works fine]
root@node:~# ip link del dev brv6
root@node:~# ip link add name brv6 type bridge
root@node:~# ip -6 address add dev brv6 scope global fdfe::401/118
root@node:~# ip link set dev brv6 up
root@node:~# ping -c2 fdfe::401
PING fdfe::401(fdfe::401) 56 data bytes
64 bytes from fdfe::401: icmp_seq=1 ttl=64 time=0.035 ms
64 bytes from fdfe::401: icmp_seq=2 ttl=64 time=0.029 ms
--- fdfe::401 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1007ms
rtt min/avg/max/mdev = 0.029/0.032/0.035/0.003 ms
root@node:~# ip link show dev brv6
13: brv6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/ether b2:75:42:d1:de:a9 brd ff:ff:ff:ff:ff:ff
Bridge with manually allocated mac address [Does not work]
root@node:~# ip link del dev brv6
root@node:~# ip link add name brv6 type bridge
root@node:~# ip link set dev brv6 address 6a:58:ea:de:65:79
root@node:~# ip -6 address add dev brv6 scope global fdfe::401/118
root@node:~# ip link set dev brv6 up
root@node:~# ping -c2 fdfe::401
PING fdfe::401(fdfe::401) 56 data bytes
From 2001:321:4321:ab:acf4::1 icmp_seq=1 Destination unreachable: Address unreachable
From 2001:321:4321:ab:acf4::1 icmp_seq=2 Destination unreachable: Address unreachable
--- fdfe::401 ping statistics ---
2 packets transmitted, 0 received, +2 errors, 100% packet loss, time 1021ms
root@node:~# ip link show dev brv6
14: brv6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000
link/ether 6a:58:ea:de:65:79 brd ff:ff:ff:ff:ff:ff
Thanks for your help.