On Mon, Dec 15, 2008 at 05:13:50PM -0500, shantanu uab wrote:
> 
> I don't know exact definition of dumpcycle and runspercycle. Here is my 
> understanding of amanda scheduling: 
> We can't specify the exact backup schedule in Amanda. However, we can tell 
> Amanda how frequently we want at least one full backup. The exact scheduling 
> can be done using crontab. 
> 
> Ref: http://www.amanda.org/fom-serve/cache/292.html 
> Example:
> dumpcycle = 1 week
> runspercycle = 5
> crontab entry: 30 2 * * 1-5 amdump 
> This tells Amanda to take at least one full backup every week (dumpcycle = 
> 1week) with 5 amdump runs (at least one run out of these would give us a full 
> backup). 
> The crontab entry will actually run the backup every weekday at 2:30 am. 
> [ Note: I am not sure whether it is the 'at least' one full backup over dump 
> cycle or thats the final figure] 
> 
> The dumpcycle and runspercycle gives Amanda an idea of frequency of backups. 
> This will help Amanda in its intelligent scheduling whether to perform full 
> or incremental backup. 
> 

I think you have the basics correct.  Where I think you are
misleading yourself is to consider each run of amdump a full
or an incremental.  Each run is a MIX of fulls and incrementals.

Amanda assumes you are backing up several or many entities
known as DiskList Entries (DLEs).  On each run, some DLEs
will get full backups the rest incrementals.

In fact, this scheme allows different DLEs to have different
dumpcycles.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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