Hi, I've installed latest version on system but I forgot that there are some VMs on the system pool. Installation has created LVM pool from scratch so it erased all data that were on the disk. I've done dd image and with inspecting I see that the data are probably still there (I can see e.g. config files contents) but I can't seem to do some recovery of the lost filesystem. Is there any posibility that it can be recovered? I've tried testdisk but it doesn't seem to see old data. Also after importing old ZFS pool it seems that there are old data (2 years ago) as when I attach image to VM and start there are files from that time. I'm sure that image are correct as I had stored it only in that exact location. Something odd happened and I don't know if it's all gone or is there any chance of recovery.. 
If somebody can suggest something I should try..
If somebody can suggest something I should try..