slam

Hi All, I stumbled across this forums and this is my first post. Hopefully someone out there experienced can help me out (thanks in advance). My friend has given me 3 x 1TB drives, basically his apprentice he sent out accidently formatted a customers DVR. The Avtech AVD717D. I work as a software developer so I thought I'd give him a hand to try and restore the data as its quite important. I have done a few things and basically I have run into a dead end and have a few questions. Does anyone know if there is a way to restore the data off the formatted drives. I tried running the drives through EaseUS Data recovery software, it detected SWF files however I cannot play them. So I think these are false positives. Mainly my questions are: 1) What file system does this unit use? Is it a linux EXT3 file system? 2) My friend mentioned that there was 3TB, upon reviewing the DVR unit. The drives can be setup in JBOD or 2+1 array (I assume its Raid 5). This will make things more tricky. I think it might still be JBOD, so maybe I can restore the drives individually. 3) I dont have the DVR, its at the clients place. Could someone let me know what happens when you do a backup to USB from that unit. Does it copy MP4 files to a USB HD? Should I be expecting MP4 formatted videos (when I restore)? 4) The USB HD you plug in, can that be an NTFS HD? or does it have to have a strict partition type? 5) Is any of the data encrypted? 6) Does anyone know any software that can help me piece back these 3 drives as a single drive and let me do a deep raw scan/restore on the data. Thanks in advance, any advice or help is greatly appreciated. Slam