From: Neil Brown <neilb@suse.de>
To: Neil Brown <neilb@suse.de>
Cc: "Pierre Vignéras" <pierre@vigneras.name>,
"Leslie Rhorer" <lrhorer@satx.rr.com>,
linux-raid@vger.kernel.org
Subject: Re: mdadm: failed devices become spares!
Date: Tue, 18 May 2010 12:06:37 +1000 [thread overview]
Message-ID: <20100518120637.24d875c9@notabene.brown> (raw)
In-Reply-To: <20100518113016.1981a08c@notabene.brown>
On Tue, 18 May 2010 11:30:16 +1000
Neil Brown <neilb@suse.de> wrote:
> On Mon, 17 May 2010 20:10:36 +0200
> Pierre Vignéras <pierre@vigneras.name> wrote:
>
> > Did I miss something, or is there something really strange happening there?
>
> Something strange...
> I cannot explain the 'SpareActive' messages.
Actually I can explain that I think.
When a device fails it gets marked as faulty, then as soon as there is no
more pending IO it gets moved out of the array. "mdadm -D" will show it with
a larger 'Number' and a 'RaidDevice' of '-'.
Normally these happen almost as a single operation, though a lot of pending
IO can slow it down.
"mdadm --monitor" identified devices based on 'Number', so it would normally
see a working device disappear - which is reported a a failure, and a
'faulty/spare' device appear, which it ignores.
However if --monitor gets to check the array between the above to events, it
will first see that the working drive is now faulty, so it reports a failure,
and then see that the faulty device isn't faulty any more and in fact isn't
even there. The "isn't event there" bit doesn't register and it treats it as
'SpareActive'.
I should fix that.
So I'm quite sure now that your devices didn't really become spares until you
removed and added them, which is exactly they way to turn failed devices
into spares.
NeilBrown
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2010-05-18 2:06 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-05-16 15:40 mdadm: failed devices become spares! Pierre Vignéras
2010-05-16 19:56 ` Leslie Rhorer
2010-05-17 18:10 ` Pierre Vignéras
2010-05-17 21:09 ` Tim Small
2010-05-18 1:30 ` Neil Brown
2010-05-18 2:06 ` Neil Brown [this message]
2010-05-18 22:25 ` MRK
2010-05-19 19:56 ` Simon Matthews
2010-05-21 21:00 ` Pierre Vignéras
2010-05-21 21:27 ` mdadm: failed devices become spares! -> Solved ! Pierre Vignéras
2010-05-18 23:07 ` mdadm: failed devices become spares! Pierre Vignéras
2010-05-19 1:45 ` Neil Brown
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=20100518120637.24d875c9@notabene.brown \
--to=neilb@suse.de \
--cc=linux-raid@vger.kernel.org \
--cc=lrhorer@satx.rr.com \
--cc=pierre@vigneras.name \
/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).