Re: document ext3 requirements

From: Robert Hancock
Date: Sat Jan 03 2009 - 18:58:47 EST


Martin MOKREJÅ wrote:
Duane Griffin wrote:
2009/1/3 Martin MOKREJÅ <mmokrejs@xxxxxxxxxxxxxxxxxxxxxx>:
Hmm, so if my dual-boot machine does not shutdown correctly and I boot
accidentally in M$ Win where I use ext2 IFS driver and modify some
stuff on the ext3 drive, after a while reboot to linux and the journal
get re-played ... Mmm ...
You *really* wouldn't want to be doing that.

The other scenario that people have reported trouble with is
suspending the system, booting a live CD which "read-only" mounts the
filesystem (and replays the journal), then resuming.

Why does not "mount -ro" die when it would have to replay the journal
with a message that user must run fsck.ext3 in order to be able to mount
it albeit read-only? Still I would prefer having an extra switch to

That would break typical system bootup in the unclean journal case, normally the root FS is mounted read-only to start with (which replays the journal) and remounted read-write later on - and usually the fsck utilities are located on the root filesystem..

force mount RO while not touching the journal for disk forensics.
I think that would also prevent the cases when a LiveCD/rescue distribution
would not mount+replay it automagically but user would really have to
provide the switch to the command. I am really not using the recovery
boot cd to touch my partitions in some cases unwillingly.

I agree, there should be a way to force it to mount "really read only" so it doesn't try to replay the journal. That might require just ignoring the journal content, which may result in the FS appearing corrupt, but for recovery/forensics purposes that seems better than nothing..
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