Re: Debian: readonly root filesystem using /dev/root

Mark Hobley wrote:

Hmmm, I am seeing something really strange on one of my Debian systems
(using Debian Testing / Lenny) , and I just wondered if anyone else is
seeing this.

My root filesystem had for some reason been mounted readonly. This was
reported to me as I tried to upgrade some packages.

I thought to myself "No problem. I will remount the filesystem for
read and write access."

I first checked that the filesystem was mounted readonly, because I
was not expecting this to be so:

cat /proc/mounts

/dev/root / ext2 ro,errors=remount-ro 0 0

Hmmm, it is readonly.

I remounted this:

mount -o remount,rw /

Right, that should have fixed this.

cat /proc/mounts

/dev/root / ext2 rw,errors=remount-ro 0 0

Ok, I created a test file:

echo hello > /root/test.fil

(Ony my system /root is the home directory for the root user, and is
on the root filesystem.)

sh: cannot create /root/test.fil: Read-only file system

Huh? The disk appears to still be readonly.

Right before a drive starts to die, it will sometimes start setting the
root partition to read only. Check dmesh, your messages log, run smart
drive tools and see if there are any errors reported. Either way,
ensure you have up to date and complete backups, regardless if you find
errors, because it probably has a matter of hours or days before data
starts being shown as unreadable (to even copy/backup) from that drive.
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