Re: [PATCH 2/3] mke2fs: print extra information about existing ext2/3/4 file systems

Lukáš Czerner
2014-05-05T14:38:37Z

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On Mon, 5 May 2014, Theodore Ts'o wrote:

> Date: Mon, 5 May 2014 10:28:08 -0400
> From: Theodore Ts'o <tytso@mit.edu>
> To: Lukáš Czerner <lczerner@redhat.com>
> Cc: Ext4 Developers List <linux-ext4@vger.kernel.org>
> Subject: Re: [PATCH 2/3] mke2fs: print extra information about existing
> ext2/3/4 file systems
>
> On Mon, May 05, 2014 at 10:04:01AM -0400, Theodore Ts'o wrote:
> > The basic idea behinid these patches is that we now get a bit more
> > context with the warning message for ext2/3/4 file systems:
> >
> > % ./misc/mke2fs -t ext4 /dev/heap/media
> > mke2fs 1.42.9 (4-Feb-2014)
> > /dev/heap/media contains a ext4 file system labelled 'media'
> > last mounted on /media on Mon May 5 08:59:53 2014
> > Proceed anyway? (y,n)
>
> And actually, the place where this context is critically important is
> in this case (where let's say, the user typo's sdc3 when they meant to
> type sdd3):
>
> % ./misc/mke2fs -t ext4 /dev/sdc3
> mke2fs 1.42.9 (4-Feb-2014)
> /dev/sdc3 contains a ext4 file system
> last mounted on /SOX-backups on Mon May 5 08:59:53 2014
> Proceed anyway? (y,n)
>
> ... where this becomes a last-ditch saving through against the
> accidental wiping of the enterprise's Sarbanes-Oxley records. :-)
>
> - Ted

Yep, it's really useful. I just was not sure what is this all about since
there was not description and I was missing context from the other patches.

But this makes me think that it would be very useful if blkid could
gather this information for other file system if possible :). This
might be very useful if we can get some overlap with other file
system with the information provided in superblock.

Karel, what do you think ?

-Lukas