-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 27/04/11 15:44, Jeffrey J. Kosowsky wrote:
> Les Mikesell wrote at about 12:08:22 -0500 on Tuesday, April 26,
> 2011:
>> On 4/26/2011 11:38 AM, Michael Conner wrote:
>>> However, another idea intrigued me that I saw in an earlier
>>> posting. Someone used a RAID 1 setup but only put in the second
>>> disk periodically, then removed it for offsite storage. I have
>>> three 2T drives, so was considering something similar where I
>>> would keep a normal 2-disk RAID 1 setup but periodically remove
>>> one disk and replace it with a prior offsite disk.
>> It is working for me, but I use a 3-member RAID1 where 2 are always
>>  connected and the 3rd is rotated out periodically.  This isn't
>> really necessary but when I was first trying it with one internal,
>> one external drive the internal one failed, corrupting the attached
>> external, and it was something of a hassle to rebuild from the
>> remaining offsite external.
> I did it that way where the 3rd 'backup' drive was mounted via USB
> and had a *catastrophic* failure where something went wrong with the
> 3rd drive causing all three RAID1 members to become corrupted. I'm
> not sure exactly what but I ended up losing 2 years of backups.

I suppose everyone has had their own experience with all these things,
but at the end of the day, this is a pure risk/benefit analysis

> I think a safer alternative would be to do what the OP proposes -- 
> that way you always have one safe copy not part of the RAID in case 
> something messes up....

In other words, you are increasing the risk of your one remaining HDD to
fail during the time that you are syncing the latest removable drive you
just plugged in. You are potentially decreasing your risk of corrupting
your RAID array due to some unknown hardware issue with a previously
used USB HDD.

As opposed to decreasing your risk to a single disk failure during a
RAID1 resync (when adding the third disk), and increasing the risk of
array corruption due to some weird code problem that you may have
experienced some time in the past...

Not to minimise the issues you had, just wanted to remind everyone to
properly analyse the risks with the different options they select.

Regards,
Adam

- -- 
Adam Goryachev
Website Managers
www.websitemanagers.com.au
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAk23svgACgkQGyoxogrTyiUNwACgiGMVAZNV593jvPdHoOCSaC+t
hLwAoJDvJZ6gS8G3K7tgVAw4MCzL1pBf
=RAb+
-----END PGP SIGNATURE-----

------------------------------------------------------------------------------
WhatsUp Gold - Download Free Network Management Software
The most intuitive, comprehensive, and cost-effective network 
management toolset available today.  Delivers lowest initial 
acquisition cost and overall TCO of any competing solution.
http://p.sf.net/sfu/whatsupgold-sd
_______________________________________________
BackupPC-users mailing list
BackupPC-users AT lists.sourceforge DOT net
List:    https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki:    http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/