Amanda-Users

Re: is excluding /usr/local/var/amanda a bad idea ?

2005-11-14 15:48:22
Subject: Re: is excluding /usr/local/var/amanda a bad idea ?
From: Jon LaBadie <jon AT jgcomp DOT com>
To: amanda-users AT amanda DOT org
Date: Mon, 14 Nov 2005 15:33:32 -0500
On Mon, Nov 14, 2005 at 07:22:23PM +0100, Stefan G. Weichinger wrote:
> Jon LaBadie wrote:
> 
> >Might not be the last file on the tape.  Suppose you collected things
> >on the holding disk, possibly several days of dumps, before taping.
> >
> >If the metadata were to hold the DLE -> tape mappings, the dump of
> >the metadata couldn't begin until after all other DLEs were taped.
> >Does that raise any issues?
> 
> The size of the metadata-DLE should be relatively predictable so this 
> amount of space could be put into calculation from start (also the 
> history should show what size to expect). The metadata-DLE could only be 
> dumped AFTER the regular DLEs are dumped completely and the related 
> indexes are written, so I assume the metadata-DLE simply gets into line 
> as soon as its ready.

What I was thinking was that many sites complete their dumping to
holding disk well before taping is complete.  For the metadata-DLE
(MD-DLE?) to be complete it needs to know what tape(s) hold what DLE's.
Thus dumping the MD-DLE would not only have to be last, but would have
to be put on hold until all other taping was complete.

It is the delay that I was concerned about.  However I guess there
is already precedence for such behavior by amdump.  The starttime
option, depending on the time argument, puts dumping on hold for
a period.  It resumes when triggered by the clock.  Perhaps the
MD-DLE could employ similar or the same code, but triggered by
completion of all other activities.


-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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