System crashes are never a positive event for a production server but the troubleshooting process doesn't have to be painful if one is aware of the processes ahead of time. InnoDB system failure issues can typically be attributed to hardware limitation or configuration errors where usable limits of buffers or logs were exceeded.
InnoDB, while typically a very stable database engine for high traffic transactional environments, is not without flaws. Sometimes buffers crash, unknown bugs occur, or other issues arise that can cause a database to suffer downtime. Luckily we can rely on ACID compliance to ensure that no data is lost in the event of a crash. If you have set InnoDB to use ACID compliant settings you will not lose data unless an external issue has occurred. External issues includes InnoDB thinking it has written data to disk but a Software RAID mechanism or RAID system using a non-battery backed cache, has not fully written changes...