ADSM-L

Re: Monthly full backups with MODE=ABSOLUTE

2005-09-02 18:53:47
Subject: Re: Monthly full backups with MODE=ABSOLUTE
From: "Allen S. Rout" <asr AT UFL DOT EDU>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Fri, 2 Sep 2005 18:53:37 -0400
==> On Thu, 1 Sep 2005 11:21:39 -0400, William Boyer <bjdboyer AT COMCAST DOT 
NET> said:

> I have a client with requirements for full monthly backups being retained
> for 7-years. 2-years ago we set them up with monthly schedules in a domain
> with the copygroups set to MODE=ABSOLUTE. Now these backups are running
> forever and I think it has to do with so many versions of the files and an
> INCREMENTAL schedule. The admin of ths shop has said that the monthly
> backups take longer each month.


> My question...would setting -INCRBYDATE help with this? These backups MUST
> be a FULL. No choice on that.


What are your retention parameters for those nodes?   If you're not separating
the monthly-full nodes from the nightly nodes, you've surely got VEREXISTS
higher than 48, right?  Is it NOLIMIT, with RETEXTRA set at 7 years?

So, somewhere between 48 and 2500 VEREXISTS [mumble]  It's an important server
else they wouldn't care.. 1M files or more, right?

Conservative target of 48M files for that one node, up to two -BILLION-
objects for the one node.  Onsite copy, offsite copy?  That's what, 230GB of
database size for one node?

Eugh.


Here's a plan: For your monthly fulls, make a new devclass ( or even a
separate server??) , inaugurate a new node every month.  Run your normal
incrementals in a sane manner, completely separately. Then every month do:

RENAME NODE monthly-thing thing-YYYY-MM
REG NODE monthly-thing boogabooga

Put it in a special stgpool, back that up to a special copypool.  Whenever a
tape gets full, check it out and stick it on the shelf. Written once, never
going to be reclaimed, why keep it near-line?  You only keep one primary
volume and one copy volume on deck, your management feels happy, and you've
kept the backups chunked sufficiently small that you can manage moving them
when it comes time to shift media format.



Might you answer their need by cutting a backupset monthly?  Then you can
store all that catalog information on shelves instead of in your DB.




- Allen S. Rout