[linux-lvm] Can't split VG which contains a thin pool

[MegaBrutal]

I also tried to pvresize, with no success.

It seems there is no way to forcefully remove the thin pool when it
has missing PVs.

Should I report it as a bug?

As for now, do you have a suggestion for a workaround? (The only
workaround I know is to dd the LV into another VG, and then destroy
the faulty VG entirely and recreate it. Maybe there is a more
convenient option to save the VG.)


MegaBrutal



2015-03-09 17:35 GMT+01:00 MegaBrutal <megabrutal at gmail.com>:
> Hello,
>
> I was trying to split a VG which has a thin pool in it. All data of
> the thin pool was residing a PV which stays in the VG. The PV I
> intended to split down only contained one LV which had no relation to
> the thin pool whatsoever.
>
> When I tried to use vgsplit, first it was telling me to deactivate the
> thin pool, and when I did that, I got this:
>
> root at thinkpad:~# vgsplit --verbose thinkvg adatavg /dev/sdb1
>     Checking for new volume group "adatavg"
>     Checking for volume group "thinkvg"
>     Archiving volume group "thinkvg" metadata (seqno 143).
>     Writing out updated volume groups
>     Archiving volume group "adatavg" metadata (seqno 0).
>   LV thinpool: segment 1 has inconsistent LV area 0
>   Internal error: LV segments corrupted in thinpool.
>
> After playing with it for a time with no success, I decided to
> forcefully remove the PV from the VG, and just disconnected the drive.
> On the origin machine, I could use "vgreduce --removemissing --force
> thinkvg" to get rid of the disconnected PV without any problem. Then I
> moved the disconnected PV to another system, which is now missing the
> other PV. I also tried vgreduce to get rid of the other PV, but I got
> this:
>
> root at blackpad:~# vgreduce --removemissing --force thinkvg
>   Couldn't find device with uuid wlyc2h-ob6Y-zZae-SIo1-JhCn-aKwG-eq2fn2.
>   Removing partial LV thinpool.
>   Cannot activate thinkvgthinpool_tmeta: pool incomplete.
>   Failed to update pool thinkvg/thinpool.
>
> It seems LVM can't really handle to split or reduce VGs which has thin pools.
>
> Any suggestions what should I do now to remove the missing PV on the other host?
>
>   LVM version:     2.02.111(2) (2014-09-01)
>   Library version: 1.02.90 (2014-09-01)
>   Driver version:  4.29.0
>
>
> Regards,
> MegaBrutal