In this little brain-splat I bring to you another backup woe – “Dropped Files”. These are an area of backup which is frequently overlooked. Many are just concerned on whether or not the backup job finished and succeeded. Many times I have seen backup reports where 1000’s of files are dropped daily as a matter of course due to lack of content exclusion base-lining.
All backups should be recursively bedded-in on initial configuration until they run for at least 99% of the time with 0 dropped files.
The danger of dropped files is that if you accept it as the norm – you will miss the critical files when they happen – Only through striving to maintain 0 dropped files through appropriate exclusions can it be possible to meet an absolute criteria of a good backup and enable you to see the real backup exceptions when they happen.
Dropped files are a critical part of the assessment on whether a backup is good so that makes it a mandatory process to eliminate any hot files and directories which are not required for a DR such as temp files and spool files. Elimination of these sources also reduces the backup payload thus reducing your backup times but also your RTO too as there is less data to restore.