From: Duncan <1i5t5.duncan@cox.net>
To: linux-btrfs@vger.kernel.org
Subject: Re: btrfs restore corrupt file
Date: Thu, 23 Nov 2017 09:25:35 +0000 (UTC) [thread overview]
Message-ID: <pan$c3b20$cd07d7e1$4b1a8f6a$c2ecab66@cox.net> (raw)
In-Reply-To: CAHzMYBQ7tsHFuHkJ5zjK6Wx0bD0XHp0TGti_uJNV5pz4ak7wJA@mail.gmail.com
Jorge Bastos posted on Wed, 22 Nov 2017 19:18:59 +0000 as excerpted:
> Hello,
>
> While doing btrfs checksum testing I purposely corrupted a file and got
> the expect I/O error when trying to copy it, I also tested btrfs restore
> to see if I could recover a known corrupt file and it did copy it but
> there was no checksum error or warning. I used btrfs restore -v
>
> Is this expect behavior or should restore warn about checksum failures?
>
> Kernel used was 4.13.13, btrfs-progs v4.13.2
AFAIK it's expected. The purpose of btrfs restore, after all, is to try
to get at least some files back from a filesystem that is generally
damaged and unable to mount, so acceptance of some possible damage to
restored files as a tradeoff for being able to restore them *at* *all* is
assumed. It's not /supposed/ to be a substitute for having a proper
backup in the first place, only something to try in case there was no
backup and getting back a damaged file is better than getting back no
file, or in case there was a backup, but it wasn't current, in which case
the restored files can be verified against the backup, and those that
differ can be examined to see if the difference is due to legitimate
change, or corruption.
--
Duncan - List replies preferred. No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master." Richard Stallman
next prev parent reply other threads:[~2017-11-23 9:25 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-22 19:18 btrfs restore corrupt file Jorge Bastos
2017-11-23 5:25 ` Chris Murphy
2017-11-23 7:43 ` Qu Wenruo
2017-11-23 9:08 ` Jorge Bastos
2017-11-23 9:25 ` Duncan [this message]
-- strict thread matches above, loose matches on Subject: below --
2017-11-22 18:46 Jorge Bastos
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='pan$c3b20$cd07d7e1$4b1a8f6a$c2ecab66@cox.net' \
--to=1i5t5.duncan@cox.net \
--cc=linux-btrfs@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.