Re: [Bobs-devel] incremental backup cleanup

[Joe Z. <jz...@co...>]

Rene Rask wrote:

>
>X should be the number of backup runs. 
>Example: Backups run on monday,tuesday,and wednesday. 
>I have chosen to keep 20 incremental backups. 20/3 is 6.6 times one week
>(7 days) which gives 46.6 days to keep backups and we round the number
>up to 47 to be safe.
>
>20/3 is the number of weeks
>times 7 is the day count.
>
>I hope this makes sense.
>  
>
It makes mathematical sense, but it's confusing and not intuitive. I 
would never guess that by looking at the configuration screen. 
Additionally, if someone changes the days of their backups, say from 3 
to 5, that shortens the retention period even though backups have only 
been running 3 times per week instead of 5. If we use this method, we 
should calculate the retention date and show that on the screen so 
people would know what it is.

>It seems like I'm wrong here. Guess we could use the find method. But
>I'd still prefer the db method. That is better if we want to do more
>advanced things in the future.
>  
>
The database method is safer and more accurate because the modification 
date in the incremental archive could be manually changed, say if 
someone moved the directory or restored it from a tape backup. I'll play 
with the database. The 'find' method was just so easy...

Cheers,
Joe