The biggest concern with a slave is to ensure your data is consistent with the master! End of story!
3 of the biggest things I see when dealing with out-of-sync slaves:
- Many users do not use the --read-only option on their slaves.
- Some of those who do often have numerous users with SUPER who can still perform writes.
- Many users simply use --slave-skip-errors=… to avoid common errors.
Of course, if you have a slave, definitely use the --read-only option.
However, SUPER users can still write on slaves with --read-only, so blindly granting SUPER to all users just to save a little time when creating users won’t help. I’d suggest to use SUPER as sparingly as possible (not to mention it’s good for security also).
And the use of --slave-skip-errors=… is generally just a quick fix to avoid errors on the slave, but a sure fire way to end up with inconsistent …[Read more]