[linux-lvm] dm-cache and snapshots

[Zdenek Kabelac]

Dne 3.11.2015 v 06:02 Syahrul Sazli Shaharir napsal(a):
> Hi,
>
> In dm-cache, how do you do snapshots on a cached LV?
>
> # lvs
>    LV         VG          Attr       LSize   Pool          Origin
>        Data%  Meta%  Move Log Cpy%Sync Convert
>    LogVol00   vg_server17 -wi-ao---- 117.19g
>    LogVol01   vg_server17 -wi-ao----  78.12g
>    kvm163_img vg_server17 Cwi-aoC---   1.05t [DataLVcache]
> [kvm163_img_corig] 10.14  12.29           0.00
>
> # lvcreate -s -n /dev/vg_server17/kvm163_img_snap -L 10G
> /dev/vg_server17/kvm163_img
>
>    Snapshots of cache type volume vg_server17/kvm163_img is not supported.

Hi

Support for snapshot of cached LV is not yet written - so you need to uncache 
LV for now.

Regards

Zdenek