Subject the joys of mysql
Author Christoph Donges
The sticky point is the database servers, where all the important
stuff is. Although we use MySQL's transactional InnoDB tables, they
can still sometimes be left in an unrecoverable state. Attempting to
bring up the master database and one of the slaves immediately after
the downtime showed corruption in parts of the database. We're
currently running full backups of the raw data on two other database
slave servers prior to attempting recovery on them (recovery alters
the data).