I spent far too much time this past week trying to find out why a Drupal was not  assigning authenticated user permissions to users who clicked on the validation link they were emailed. Instead, it would simply remove the temporary unverified user permission.

It's supposed to do the latter, but then also follow it up with the former. It turns out the problem was a Drupal bug that was triggered by my MySQL setup.

In order to rule out a crap power infrastructure as the cause for some naughty server behaviour on a client site, it was suggested I should stick a UPS on said server, to make sure that at least the input power would be clean.

In a confusion of Andys I found a recommendation for the APC BackUPS CS 500, so that is what I got and installed.

With apcupsd installed on Debian Etch, the UPS is immediately detected and it "just works".

A while ago Arjen Lentz blogged about transient MySQL errors that can occur when using a transactional storage engine, like say InnoDB.

Since I'm a fan of the reliability and automated recovery that InnoDB provides, I use it for all the Drupals that I host.  However, on a very busy site, this may lead to deadlocks. These in turn lead to users seeing errors, which is something I'd like to avoid. Especially if the error could be prevented.