Tom Horsley writes:
Not all of it though, there were still a few more things for google to turn up (like setting bridge.stp making it start 100 times faster).
I do have a server with a bridge and a hosted VM that uses it. The server predated the existence of NetworkManager. At some point in the past I just removed
NM_CONTROLLED=NO
from /etc/sysconfig/network-scripts/ifcfg*, I just checked and nmcli returns "bridge.stp: no", in this situation.
The server takes an eternity to boot, but not because of this setting…