Get fsfreeze in Ubuntu

I pulled fsfreeze from current HEAD of util-linux (git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git 260d3cf7f30c) and put that into util-linux. Then built, and tried running it.

First, I did:
$ sudo fsfreeze --freeze / ; sudo fsfreeze --unfreeze /
I hoped that the second would get run after the first, and even if i lost keyboard input or something I'd still unfreeze.

Instead, the system completely froze.
Then, after rebooting, I tried:
$ mount /dev/sda8 /mnt
$ sudo fsfreeze /mnt

The same thing happened.

So, I'm all for getting 'fsfreeze' and its function into Ubuntu (and ideally natty), but it seems like it isn't as trivial as just grabbing 2 files.

If you want to test, but not build, I uploaded to my ppa also: https://launchpad.net/~smoser/+archive/ppa

Note that you shouldn't use fsfreeze on a filesystem where there is lots of IO - notably, rootfs (/).

If you do so, all programs write-accessing it will be "frozen" as well, which could explain your system freeze.

Try doing it on a filesystem which is not the main one, like /boot, or similar (i.e. /var/lib/mysql, if it's a separate partition).

If "sudo fsfreeze --freeze / ; sudo fsfreeze --unfreeze /" is expected to freeze the system hard is a different question - perhaps someone should ask on a linux-fsdevel or similar mailing list.

http://vger.kernel.org/vger-lists.html#linux-fsdevel

Status changed to 'Confirmed' because the bug affects multiple users.

just for the record, on precise:
 $ dpkg -S /sbin/fsfreeze
util-linux: /sbin/fsfreeze
 $ dpkg-query --show util-linux
util-linux 2.19.1-2ubuntu3

Additionally, on an EC2 t1.micro instance of 'ami-410bc128' (us-east-1/ebs/ubuntu-precise-daily-amd64-server-20111212'), I just did:
$ sudo sh -c 'date; fsfreeze --freeze /; fsfreeze --unfreeze /; date'
Mon Dec 12 22:15:23 UTC 2011
Mon Dec 12 22:15:23 UTC 2011
ubuntu@ip-10-202-206-73:~$ uname -r
3.2.0-4-virtual
ubuntu@ip-10-202-206-73:~$ cat /proc/version_signature
Ubuntu 3.2.0-4.10-virtual 3.2.0-rc5

Then, just for fun
$ sudo apt-get clean
$ sudo sh -c 'apt-get update > /tmp/apt.log & sleep 2 ; date; fsfreeze --freeze /; fsfreeze --unfreeze /; date'
Mon Dec 12 22:19:27 UTC 2011
Mon Dec 12 22:19:27 UTC 2011

I redirected to /tmp/apt.log to show additional fs writes going on, and also to make output prettier. (otherwise the 'date' output is mixed with the apt output).

So, to me, this is fix-released.

I just verfied this is also functioning on released oneiric image
$ sudo sh -c 'apt-get clean; apt-get update >/tmp/apt.log & sleep 2; date; fsfreeze --freeze /; echo $?; fsfreeze --unfreeze /; echo $?; date'
Mon Dec 12 22:34:33 UTC 2011
0
0
Mon Dec 12 22:34:33 UTC 2011

$ lsb_release -c
Codename: oneiric
$ cat /etc/cloud/build.info
build_name: server
serial: 20111211