On Friday 01 April 2005 03:19, Erik P. Olsen wrote:
[...]
>Hm. I would like to challenge this statement. It may be true if you
> have a large network of systems to back up but if you only have one
> system I doubt if it's true. Before my switch to Linux I backed up
> my system (OS/2) on a weekly schedule with one full back-up and
> four incremental back-ups to one tape only.
If useing tapes, and they are big enough, set the holding disk
reserved value to some low percentage like 20%, and only put in a
tape once a week, with the autoflush option set in your amanda.conf.
That will put the whole weeks worth of backups on one tape. It does
have the disadvantage of leaving that weeks stuff subject to a disk
failure though. But thats something I've not had in about 2 years,
no failures out of about 7 drives here when they are all spinning.
But I'll lose one yet today just because I mentioned it, Murphy is
listening. :(
> It worked extremely
> well, if I crashed my system - which I did very often - it took me
> about half an hour to recover either using a stand-alone recover
> program or my maintenance OS/2 if it was alive and I kept an
> archive of up to 8 weeks of back-ups.
I was always told that OS2 was stable. And I stay quite bleeding edge
in terms of the kernel I run on this FC2 system, which is also
backing up my RH7.3 firewall box. Currently running 2.6.12-rc1, the
smoothest running, snappiest kernel yet in the 2.6 series. I can't
recall the last time I actually crashed a running system. Several
months ago in any event.
> Now with Linux and Amanda I
> use 9 tapes mainly because Amanda won't add today's back-up to
> yesterday's tape.
Thats a security risk amanda won't take. When amanda is done, and has
released the drive, there is nothing to prevent someone from removing
the tape, and either reinserting it, in which case the tape is
rewound and will be totally overwritten, or even the wrong tape might
be reloaded. Either way, amanda has no ironclad assurance that the
tape will be sitting in the same position it was left in, ready to
append new files to it. Yes, most drives today can do an 'mt
-d/dev/nst0 seof' and hit within a quarter of an inch of it. But
some drives cannot, and that locks amanda out of useing that feature
for all users. At some point, the last legacy drive that cannot do
that might die, but we have no idea when that might be...
Maybe that should be the subject of a questionaire at some point?
> I could probably do with less tapes but I feel
> more confident with a large tape pool.
[...]
I answered this in a previous post.
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
99.34% setiathome rank, not too shabby for a WV hillbilly
Yahoo.com and AOL/TW attorneys please note, additions to the above
message by Gene Heskett are:
Copyright 2005 by Maurice Eugene Heskett, all rights reserved.
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