Of course, you could always *not* yank them; instead just fail them
(after unmounting/syncing/whatever) and leave the actual disk in the
machine.

Purists would likely argue this isn't true backup or something, but
backup can be taken to different extremes - it all depends on what
risks you want to protect yourself against.

If you don't care about location-based risks (eg fire), then I don't
see why you would bother removing the drives. Leaving disks in the
machine basically only protects you against 'oops' moments (rm -rf and
such like)., but not much else.

The advantage in RAID1 is that it makes a copy constantly, so it takes
no time to create the backup - using other methods (rsync, tape,
rdiff-backup) with a huge amount of data, this time can be
prohibitive.

Also, I'd say that plugging/unplugging disks would historically be a
problem, but SATA shouldn't be, IMO. Also, there are solutions
specifically designed for plugging/unplugging - which makes the point
moot - so you might consider one of those.

Having saidd that, this is Just my opinion, and I'm no expert...

Max.

2008/11/20 Drew [off-list ref]:

On Wed, Nov 19, 2008 at 12:13 PM, Linux [off-list ref] wrote:

quoted

quoted

In recent months I've been exploring low cost solutions for backing up
the data on my home media server. I already run three raid-1 arrays on
this rig to protect against drive failures and a fellow linux user
suggested I consider using the existing raid, just yank the 'backup'
disks as needed, and drop in fresh disks to replace the yanked unit.

I guess this is a little risky. Plugging disks too often does not  sound good.
Is "rsync" not enough for you?

A year ago my old 10GB Travan & 4 tapes was enough to backup my OS and
data. In the last year I've seen my data storage jump from 40GB to 2TB
courtesy of a MythTV installation. I'm still figuring out how to
manage this large an amount of data and backup solutions are now on
the table as it's been indicated to me that loss of important 'media'
will result in a greatly lowered WAF(*).


--
Drew

"Nothing in life is to be feared. It is only to be understood."
--Marie Curie

(*) WAF: Wife Acceptance Factor
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