On 23.09.2019 3:40, Mark Fletcher wrote: > Hello > > While setting up a newly purchased RAID-capable hard disk cage I've > damaged the contents of 2 hard disks and want to know if it is possible > to recover. > > The cage has 5 disk slots each occupied by 3TB hard disks. 4 of the > disks came from an older cage by the same maker (TerraMaster, in case it > matters) and one is new. > > In the old configuration I had 2 disks in a RAID 1 configuration and 2 > as single disks. I transferred over the 4 disks from the old cage and > added a new disk in the 5th slot. > > The new cage is RAID 1 capable in its first two slots and the remaining > three are single disks. > > You've probably guessed what I did by now. I put the two single disks > from the old cage into the first two slots of the cage and enabled RAID. > I should have put the two disks that were RAID in the old cage in those > slots. > > I realised almost immediately what I had done and swapped the disks > around into the correct configuration. My originally-RAID pair are now > correctly in the first two slots with RAID enabled and are none the > worse for the experience of having briefly having been in the single > slots. Unfortunately my two originally-single disks are showing up as > having no partitions according to lsblk. > > There was data on those disks that I would ideally like to get back. Do > I have any hope of undoing whatever damage was done to the disks when > the cage was switched to RAID mode? I did not write any data to them, > and crucially I did NOT create a new file system on the disks after > turning on RAID in the cage before realising what I had done. > > A search turned up the gpart program but it looks ancient -- could it > still help me? gparted may also help but most online info about it is > about repartitioning disks to prepare for a dual-boot install, not about > recovering a messed-up partition table (which is what I assume I am > dealing with here). > > The disks were originally formatted ext4 with a single partition taking > the whole of the disk. Since no file system was created on them and no > data was written to them while they were in the RAID slots of the cage, > I'm hoping I can repair things, but looking for ideas of where to start. > > Thanks in advance and in hope > > Mark > > PS Running buster if that's important > If I understood this right, you have two disks with data and they were previously configured as RAID1 volume. What make\model RAID-controller do you use? Because "cages" by themselves offer only SATA\SAS ports for disks to connect them. RAID functionality is provided by OS (software RAID), or RAID-controller (hardware RAID).
I suggest you to make byte-by-byte image from one of those disks, so you won't damage the data further and work only with image. You can use data recovery software from R-TT called R-Studio [1] to raw-scan disk images for partition signatures and recover previous partition with data that is still on them. AFAIK it could be used in preview-only mode without license. It can reassemble\reconstruct RAID with various configurations (disk groups, stripes size, etc). Despite my previous experiences with R-Studio I have vague knowledge about its ever-changing licensing and difference in features for its many versions, so you have to consult about that with their sales reps. [1] https://www.r-studio.com/ -- With kindest regards, Alexander. ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ Debian - The universal operating system ⢿⡄⠘⠷⠚⠋⠀ https://www.debian.org ⠈⠳⣄⠀⠀⠀⠀
