Re: [gentoo-user] fsck separate /usr

[Alex Schuster <wonko@wonkology.org>]

Philip Webb writes:

> 120513 Alex Schuster wrote:
> > I'm using the new udev with a separate /usr partition ...
> > after an unclean shutdown
> > -- reading files in /proc/<pid>/ was not a good idea --
> > /usr wants to be fsck'ed. But it is already mounted at that stage.
> > Maybe I should just enlarge my root partition and move /usr there
> 
> Did you see my description of how I did that ? -- see list 120506 .
> The actual process took me  2 h 30 m , but preparations spread out
> longer. Everything else is working just as before,
> but I don't have to bother ever about Initramfs (whatever that is :
> smile), & can update Udev without any worries when it becomes stable.
> HTH

I saw that, but here it will be much easier. All is on LVM here, so this should do it:

# enlarge root partition
lvresize -L +17G /dev/weird/root
cryptsetup resize root
resize2fs /dev/mapper/root

# make sure /usr is not being written to. For other partitions, I'd
# create an LVM snapshot
mount -o remount,ro /usr

# mount root to another place, without mounts like /usr showing up there
mkdir /tmp/bindroot
mount -o bind / /tmp/bindroot

# copy data over
rsync -ax /usr /tmp/bindroot/

# remove /usr stuff from fstab and dmcrypt
sed "/\/dev\/weird\/usr/ d" /etc/fstab
sed -i "/^target=usr2$/{N;N:N:d}" /etc/conf.d/dmcrypt

# done!
reboot

No need for downtime except for the reboot, I guess I cannot unmount /usr
otherwise.

	Wonko