On Fri, Oct 20, 2006 at 03:50:25PM -0700, Don Murray wrote:
> 
> Hello list,
> 
> I've been lurking on the list a few days (not really long enough to be 
> opening my mouth, but here it goes).
> 
> I am a relatively novice sysadmin looking for a better backup setup than 
> our handcrafted scripts.  Amanda looks interesting but I am worried that 
> it will not necessarily solve my problem.  So I was hoping to beg your 
> indulgence for a moment and see if anyone has any advice for me.
> 
> My main concern is that we have to be "up" round the clock these days as 
> we have people connecting during their work day, 9 hours different from 
> ours.  So having major services disrupted in the middle of the night for 
> backups doesn't seem a viable solution anymore, as it hits the other 
> people in the middle of the day.

"Up" is less a concern to me than "connected".  Are some of these
people working on laptops or other computers that are not accessible
to your backup server except at certain times?

Let's assume not, that all are connected when you want to do backups.

> 
> We are a small business.  We have 2 main linux servers each with about 
> 200G to back up.  Backing up a full 200G volume across the network takes 
> about 7 hours currently.
> 
> I understand from the documentation that Amanda will attempt to balance 
> the time taken for backups through its scheduling process.  However, it 
> seems to me that when you have to do a level 0 of size X, you have to do 
> it, and so you will take the full 7 hours.
> 
> The bad news is that currently these systems are set up with the full 
> 200G on single partitions.
> 

If you are willing to use tar as as your backup program (many, many
amanda sites do that) then there is not problem.  You say you have
basically 400GB of data.  The basic unit of backup for amanda is
called a "DiskList Entry" (DLE) after the name of a config file.
With tar as the backup program you can specify directory tree's
as a DLE rather than filesystems.  So you could have a DLE for
/boot, /var, /home, /usr/local, /usr (without local), /opt,
/database, and one for / without all the others.  This is done
by "including" or "excluding" files and directories in the DLE
config.  Now with 16 DLE's from two systems (or even more is you
wish), amanda can spread the level 0's of those 16 items over
your dumpcycle (typically a week).  So on a typical day, only
2 or 3 of the DLEs will get a level 0 and on average your daily
backups will be 1/7th of your 400GB or about 60GB/day.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
 4455 Province Line Road        (609) 252-0159
 Princeton, NJ  08540-4322      (609) 683-7220 (fax)