On Sat, Mar 26, 2016 at 12:39 AM, Chris Murphy <lists@colorremedies.com> wrote:
>
>
> On Fri, Mar 25, 2016, 4:46 PM thibaut noah <thibaut.noah@gmail.com> wrote:
>>
>> That brings the question, how to shrink the VG containing home since it
>> apparently needs to be unmount?
>>
>> H
>
>
> *sigh* I can't help myself and point out how much easier this is on btrfs.
> 'Btrfs dev remove' and it moves your data to remaining devices, shrinks the
> fs, and removes the requested device, all online, one command, fast, safe.
> But this is off topic and doesn't help.
>
> You're kinda stuck. You'll have to boot off live media and install
> blivet-gui to see if it supports all of this. Or if you'll have to do it by
> command line.
>
> vgmerge
> e2resizefs
> lvresize
> pvmove -n  ## specify the home LV
> vgreduce

I suggest substituting e2fsresize and lvresize with fsadm. It combines the steps, and also does an fsck first. It takes the form:
# fsadm -v -l -y resize /dev/VG/testext4 25g

That's really the only step you need the live boot for, the pvmove step can be done while the file system being moved is in use, and also vgreduce.

Also, pvmove can be slow, so you might want to use -i option with a value of say 30, to get an update every 30 seconds. Compare pvs 'PFree' for the SSD and lvs 'LSize' for home to make sure there's enough room on the SSD to move the LV over, otherwise pvmove won't work (or at least it won't completely move everything over). So you'll want to get the resize step correct.


--
Chris Murphy