[linux-lvm] what will happen with lvconvert merge after reboot?

[Zdenek Kabelac]

Dne 10. 08. 20 v 1:19 Tomas Dalebjörk napsal(a):
> hi
> 
> If a user starts a
> # lvconvert --merge -b snaplv
> 
> and reboots the server before the convert/merge has completed
> 
> will the merge/converting process continue after reboot?
> or will the volume be stale?
> 
> if the merge/convert is restarted, can it resume where it was?
> 

Hi

Merge 'starts' when origin&snap device are unused.
Once snapshot merge start - it cannot be reverted.

If there is any sort of 'failure' (i.e. poweroff) - merging continue
after reboot and should safely finish.

Note - once the merge starts - you can already use 'merged' LV since merging 
is running in the background (blocks are copied and you can 'monitor' its 
status with  'lvs' command).

If you would be using 'thin' snapshot - merge is an instant operation.

Regards

Zdenek