It appears lxd fails to start on a system running the linux-kvm kernel, due to a netlink issue:
Oct 13 20:40:53 builder lxd-bridge.start[448]: RTNETLINK answers: Operation not supported
Oct 13 20:40:53 builder lxd-bridge.start[448]: Failed to setup lxd-bridge.
Oct 13 20:40:53 builder systemd[1]: lxd-bridge.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
I don't know what specific operation lxd is looking for with its bridge. strace shows:
[pid 531] open("/usr/lib/ip/link_bridge.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
[pid 531] sendmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"<\0\0\0\20\0\5\6g%\341Y\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 60}], msg_controllen=0, msg_flags=0}, 0) = 60
[pid 531] recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"P\0\0\0\2\0\0\0g%\341Y\23\2\0\0\241\377\377\377<\0\0\0\20\0\5\6g%\341Y"..., 32768}], msg_controllen=0, msg_flags=0}, 0) = 80
[pid 531] write(2, "RTNETLINK answers: Operation not"..., 43RTNETLINK answers: Operation not supported
) = 43
lxd is important to support on linux-kvm.
@Steve, please try this test kernel, which has CONFIG_BRIDGE enabled:
http://