If you’re a DBA, one of your “easiest” tasks is to stop/start
MySQL during a maintenance window, but even that could lead to
unwanted scenarios if you modify some dynamic parameters at some
point in your instance.
Here’s a brief story of how this could happen, to make it
clearer:
You’re a DBA managing a few MySQL servers. The application using
one of them starts having issues on a Friday night, right before
it’s time to leave; after a quick check, you notice the app is
requesting more connections, and the hotfix is to up max
connections; you change them dynamically, the fire is off, and so
are you. Let your future self worry about finding the root cause
and fixing it properly the following Monday.
But life happens; Monday is here with new challenges, and you
already forgot about the connections issue… A few months later, a
restart for MySQL is required, and surprise, surprise, right
after …
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