Some operational notes

[mark]

When doing a global master change...

* don't forget MogileFS
* stop all jobs, if anybody is still up with the old config (TheSchwartz workers!) they will continue writing to the old master
* take the old master hard-offline and leave it that way to flush out any bad behavers? at least monitor show processlist
* don't forget all slaves (mailserver slave)

Todo: figure out if there's a way to put a MySQL server fully read-only (except for replication?), I know there's a read-only config file option but I don't think it works as expected.