linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Eyal Lebedinsky <eyal@eyal.emu.id.au>
To: Alberto Alonso <alberto@ggsys.net>
Cc: linux-raid@vger.kernel.org
Subject: Re: Software RAID when it works and when it doesn't
Date: Sun, 14 Oct 2007 08:46:04 +1000	[thread overview]
Message-ID: <47114AAC.4000903@eyal.emu.id.au> (raw)
In-Reply-To: <1192300851.16416.265.camel@w100>

RAID0 is non redundant so a disk failure will correctly fail the array.

Alberto Alonso wrote:
> Over the past several months I have encountered 3
> cases where the software RAID didn't work in keeping
> the servers up and running.
> 
> In all cases, the failure has been on a single drive,
> yet the whole md device and server become unresponsive.
> 
> (usb-storage)
> In one situation a RAID 0 across 2 USB drives failed
> when one of the drives accidentally got turned off.
> 
> (sata)
> A second case a disk started generating reports like:
> end_request: I/O error, dev sdb, sector 42644555
> 
> (sata)
> The third case (which I'm living right now) is a disk
> that I can see during the boot process but that I can't
> get operations on it to come back (ie. fdisk -l /dev/sdc). 
> 
> (pata)
> I have had at least 4 situations on old servers based
> on pata disks where disk failures where successful in
> being flagged and arrays where degraded automatically.
> 
> So, this is all making me wonder under what circumstances
> software RAID may have problems detecting disk failures.
> 
> I need to come up with a best practices solution and also
> need to understand more as I move into raid over local
> network (ie. iscsi, AoE or NBD). Could a disk failure in
> one of the servers or a server going offline bring the
> whole array down?
> 
> Thanks for any information or comments,
> 
> Alberto

-- 
Eyal Lebedinsky	(eyal@eyal.emu.id.au)

  reply	other threads:[~2007-10-13 22:46 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-10-13 18:40 Software RAID when it works and when it doesn't Alberto Alonso
2007-10-13 22:46 ` Eyal Lebedinsky [this message]
2007-10-13 22:50 ` Neil Brown
2007-10-14  5:57   ` Alberto Alonso
2007-10-16 21:57     ` Mike Accetta
2007-10-16 22:29       ` Richard Scobie
2007-10-17 21:53       ` Support
2007-10-18 15:26       ` Goswin von Brederlow
2007-10-19  7:07         ` Alberto Alonso
2007-10-19 15:02           ` Justin Piszcz
2007-10-20 13:45             ` Michael Tokarev
2007-10-20 13:55               ` Justin Piszcz
2007-10-26 16:11             ` Goswin von Brederlow
2007-10-26 16:11               ` Justin Piszcz
2007-10-23 22:45           ` Bill Davidsen
2007-10-24  5:50             ` Alberto Alonso
2007-10-24 20:04               ` Bill Davidsen
2007-10-24 20:18                 ` Alberto Alonso
2007-10-26 16:12                 ` Goswin von Brederlow
2007-10-26 17:09                   ` Alberto Alonso
2007-10-27 15:26                     ` Bill Davidsen
2007-11-02  8:47                       ` Alberto Alonso
     [not found] ` <471241F8.50205@harddata.com>
2007-10-14 18:22   ` Alberto Alonso

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=47114AAC.4000903@eyal.emu.id.au \
    --to=eyal@eyal.emu.id.au \
    --cc=alberto@ggsys.net \
    --cc=linux-raid@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).