Old Version Cleanup Rules
What is the correct setting to have the program auto-delete old backup versions. I want it to delete older Incremental & Full Backups automatically. I have to manually delete the older versions to free up space on my NAS. I have included a screenshot of my current settings.
Craig, welcome to these public User Forums.
Your settings look to be correct but there are common misconceptions about automatic cleanup that can cause confusion.
Automatic cleanup
There can be lots of confusion around the topic of automatic cleanup which can be better understood if some basic concepts are known!
First: automatic cleanup only works on complete(d) versions / version chains. Do not expect individual elements of version chains to be cleaned up, such as incremental or differential files!
Second: automatic cleanup only runs after a new Full backup for the next version / version chain has been created successfully. This means that there must be sufficient free space available on the storage drive / location to hold a new Full backup image file!
Third: counting of days does not start until after a new Full backup file has been created when using the option to ‘Delete versions / version chains older than X days.’ It does not start for the active backup version / version chain before that point!
Fourth: the simplest & easiest automatic cleanup option to use & understand is to ‘Store no more than X recent versions / version chains.’ The criteria here means that if you set X = 2, then when the X+1 (3rd) version / version chain is created successfully with a new Full backup file, then the oldest version / version chain will be deleted by automatic cleanup.
Example:
Incremental backup task, using Full plus 5 Incremental backups before next new Full backup.
Task scheduled to run daily with automatic cleanup set to ‘Store no more than 2 version chains.’
Day 1 – Full backup created.
Days 2 – 6 Incremental backups created.
Day 7 – Next new Full backup created.
Days 8 – 12 Incremental backups created.
Day 13 – Next new Full backup created. Automatic cleanup deletes files created on days 1 – 6.
If the same task used ‘Delete version chains older than 7 days’, then those 7 days wouldn’t start counting until day 7 for the first set of files (version chain 1) and not until day 13 for the second set etc. So automatic cleanup wouldn’t delete the oldest chain until day 14 in the above example.