From mboxrd@z Thu Jan  1 00:00:00 1970
From: Phil Turmel <philip@turmel.org>
Subject: Re: Data Offset
Date: Wed, 13 Jun 2012 14:11:58 -0400
Message-ID: <4FD8D7EE.5000805@turmel.org>
References: <CAFhY2CjOECFy4bWDL6zs9rtSkVGPR9Wv=1UX9vKgmdjwMsmBYg@mail.gmail.com> <20120602095237.3822e2c2@notabene.brown> <CAFhY2Cjwep5mZkYCfRn4UYmQpSyHU13dSCB8HF8F9wG8Rzx9Aw@mail.gmail.com> <20120604133526.6da3bf10@notabene.brown> <4FCCFDBB.201@pierre-beck.de> <20120605085728.7e922359@notabene.brown> <CAFhY2CjQAutSxzJ-7e+G-1Jw-U6JsFjBBHOmiqOxkhkZy6kd9g@mail.gmail.com> <20120605154427.192566af@notabene.brown> <CAFhY2CiDTMRSV2wFCMhT9ZstUkHkJS7E0p7SP-ssfqwaquo+0w@mail.gmail.com> <20120610074531.65eaed81@notabene.brown> <CAFhY2CgxkjH6JvJzvQt9XT0oawntK7YoTFqnXQJGzvqthD8XpQ@mail.gmail.com> <4FD86179.1080209@pierre-beck.de> <4FD88C50.1000104@turmel.org> <4FD8D439.10406@pierre-beck.de>
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To: Pierre Beck <mail@pierre-beck.de>
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On 06/13/2012 01:56 PM, Pierre Beck wrote:
> Am 13.06.2012 14:49, schrieb Phil Turmel:
>>
>> fsck -n is the *only* safe way to automate the check.  Hex dumps of
>> expected signature blocks is even better, but is difficult to automate.
> 
> The journal playback seemed less dangerous than fsck in general, but
> fsck -n is even better, agreed.

It's not a question more or less dangerous.  If the stripes are out of
order, writing to the array is destructive.  Not only will the writes
probably land in the wrong place on the device, but writing triggers
recalculated parity, which also probably stomps on other data.

Phil