Re: [gentoo-user] Merging separate /usr back into / - one last time...

On Mon, Dec 02 2013, tanstaafl@×××××××××××.org wrote:

> Is rsync -a enough for my relatively simple system setup, or would
> using any or all of the other options suggested in those threads be
> safer/better? Specifically:
>
> -a, or -axAHX, or -apogXx, or -PvasHAX

I am not an expert but here goes.
-x would not hurt but should not be needed since i believe that your
current /dev/vg/usr is just one partition.

I didn't need -X -A because I don't have acls or extended attributes

> or should I go with a combined -apogsvxAHPX ?
>
> So, here's the plan, please check me...
>
> 1. Boot off of the latest gentoo LiveDVD
>
> 2. Mount / and create new /usr directory

I am missing something.  I would have thought your old / (dev/sda3)
already has an empty /usr directory where you previously mounted
/dev/vg/usr

> mount /dev/sda3 /mnt/gentoo/
> mkdir /mnt/gentoo/usr
>
> 3. Mount old /usr to be moved/merged
>
> vgscan
> vgchange -a y
> mount /dev/vg/usr /mnt/gentoo/oldusr
>
> 4. Copy /oldusr to /usr

This suggests that your current root (dev/sda3) is big enough to
include the previous /usr (dev/vg/usr).  That is indeed a simple case.
Many of us had to move partitions around to get a big enough partition
for / + /usr.

> rsync -a? /mnt/gentoo/oldusr/ /mnt/gentoo/usr/
>
> Are the trailing slashes required/important/necessary?

The first trailing slash (oldusr/) is important.  Without it, you would
be creating the directory /mnt/gentoo/usr/oldusr.  With it (as you
wrote) just the contents of /oldusr are copied not the directory itself.
So yes you want that slash.

I don't believe the 2nd trailing / (usr/) is needed, but doesn't hurt.
The rsync man page shows both uses and I don't see any words saying
anything about the difference.  I must say I never noticed the two
different uses in the man page can't remember what I used.  But again, I
believe the results are the same.

> Which arguments should I use?

Discussed above

> 5. Edit /etc/fstab and comment/remove the /usr line
>
> nano -wc /mnt/gentoo/etc/fstab
>
> #/dev/vg/usr       /usr        reiserfs        noatime         0 0
>
> 6. Unmount mounted filesystems
>
> umount /mnt/gentoo/oldusr
> umount /mnt/gentoo
>
> 7. Reboot into new system
>
> Done?
>
> I'm pretty sure that:
>
> 1. There is no need to chroot into the real system during this process,
>
> and
>
> 2. I only need to mount / and the old /usr, no need to mount anything
>    else (/proc, /sys, /var, /home, activating swap, etc)
>
> Correct?

Both of these seem correct to me.

Good luck!

allan