From: "H. Peter Anvin" <hpa@zytor.com>
To: Neil Brown <neilb@suse.de>
Cc: Doug Ledford <dledford@redhat.com>,
Peter Rabbitson <rabbit+list@rabbit.us>,
linux-raid@vger.kernel.org
Subject: Re: Proper partition type for components with V1.x superblocks?
Date: Mon, 07 Jul 2008 10:38:52 -0700 [thread overview]
Message-ID: <487254AC.7040106@zytor.com> (raw)
In-Reply-To: <18545.35548.800516.532854@notabene.brown>
Neil Brown wrote:
>
> But if you use 1.0, then some well-meaning install program might mount
> one drive from a raid1 as a filesystem, write to it, and get your RAID
> all out of sync.
>
One more thing on this: this is actually fine as long as the RAID code
detects the out-of-syncness. This can't be foolproof, of course, but
for virtually all filesystems there is *something* in the first megabyte
or so (usually within the first 128K) that is touched by almost every
write -- the superblock, or its equivalent.
If the RAID code did a sanity check on the first megabyte, it would
catch the vast majority of all unintentional desynchronization events.
-hpa
prev parent reply other threads:[~2008-07-07 17:38 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-11 9:26 Proper partition type for components with V1.x superblocks? Peter Rabbitson
2008-06-11 11:23 ` Andre Noll
2008-06-11 12:12 ` Peter Rabbitson
2008-06-11 21:06 ` Andre Noll
2008-06-11 11:24 ` David Greaves
2008-06-11 11:35 ` Peter Rabbitson
2008-06-11 23:52 ` Neil Brown
2008-07-02 22:02 ` H. Peter Anvin
2008-07-03 5:17 ` Doug Ledford
2008-07-07 3:17 ` Neil Brown
2008-07-07 14:02 ` Doug Ledford
2008-07-07 17:33 ` H. Peter Anvin
2008-07-07 17:32 ` H. Peter Anvin
2008-07-07 23:10 ` David Greaves
2008-07-07 23:47 ` H. Peter Anvin
2008-07-07 17:38 ` H. Peter Anvin [this message]
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=487254AC.7040106@zytor.com \
--to=hpa@zytor.com \
--cc=dledford@redhat.com \
--cc=linux-raid@vger.kernel.org \
--cc=neilb@suse.de \
--cc=rabbit+list@rabbit.us \
/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).