On Saturday 26 September 2020 08:54:46 Dave Sherohman wrote:

> On Sat, Sep 26, 2020 at 01:35:51PM +0100, J Martin Rushton wrote:
> > If your law school is using TSM, then the only use for Amanda would
> > be to back up the small machines onto the central server, and then
> > TSM can migrate (HSM) or backup to tape/slow disk.
>
> Guess my overview of the history and organizations involved was a bit
> too brief...
>
> My department is the central university library.  We're not officially
> affiliated with the law school, they just offered backups as a service
> when they set up their own backup system, and we contracted with them
> to purchase that service.  But now we want to terminate that contract
> and start handling backups ourselves, within the library's own IT
> group, which will remove both TSM and the law school from the picture
> entirely.

Which amanda can do. The problem we see most often is how amanda goes 
about scheduling those backups as it does not use a fixed schedule. It 
will do a full of a given Disk List Entry, called a DLE, within the time 
period its told to, but within that time period, it will shuffle the 
order around to attempt using about the same amount of media each run.  
This was valuable when smaller tapes and less than reliable drives were 
the norm, but not so much today with the advent of huge hard drives that 
are hundreds of times more dependable and the tapes turning into 
directories per run, and files within those directories. Amanda tracks 
all that so you don't have to. But amrecover can restore a previous 
version of a file if it needs to also.

Commercial time, but no money involved.

I've written a wrapper, and you may have to edit it a bit to suit your 
needs, a GenesAmandaHelper which allows amanda to do a bare metal 
restore to the state the system was in at the completion of the just 
completed run, whereas that situation without my wrapper loses a runs 
data because the recorded index could be from yesterdays run. My scripts 
attach both the index data, including that generated by the just 
completed run to the end of each run, and also the amanda configuration 
that made that backup.  This is a considerable amount of data that would 
be missing from amandas database in the event the drive holding it went 
toes up. That extra file from last nights run is currently 594,288,640 
bytes of data here for the 5 machine backup from last night and is the 
indice data from 60 vtapes on a 2TB drive.  All of it.  The backed up 
configuration OTOH is only about 12k, but if the drive it lives on 
expires, you've still got a working config on the /amandatapes drive in 
the Dailys/data directory.

And I sleep better.

Copyright 2020 by Maurice E. Heskett
Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>

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