If you open a port in the server 2003 firewall, be prepared for some things to silently fail, such as database replication: apparently a weird ‘reset’ is sent to everything that’s connected, but it doesn’t seem to work properly so some apps think their TCP connections are still established (such as MySQL). This can then cause your DB’s to quietly go out of synch… ouch.
Restart MySQL and it’ll catch up with the master.
