June 9, 20197 yr I recently had the USB Flash Drive fail while moving houses, the USB was actually severed in half (see pic), so no way I was going to recover the necessary config files In summary I have 1x 60GB SSD Cache and 4x 2TB Drives, my understanding was once I've setup a new USB Drive this should've just come back online O.K. given it is a 4x Disk setup with 1x Parity... which it did to some extend except for Disk 2 (see below) Cache KINGSTON_SV300S37A60G_50026B723301B685 - 60 GB (sdf) - btrfs Parity ST2000DM001-1CH164_Z1E4L0GQ - 2 TB (sdb) Disk 1 ST2000DM001-1ER164_Z4Z0JPET - 2 TB (sde) - xfs Disk 2 ST2000DM006-2DM164_W4Z2XYVD - 2 TB (sdd) - Unmountable: No file system Disk 3 ST2000NM0033-9ZM175_Z1X5GSAQ - 2 TB (sdc) - xfs I've gone to Tools > Diagnostics and did an export of the disk having problems (see attached), I'm not very good at reading these output logs, can someone please help and point in the right direction as I can see chunks of data missing which will probably be on this drive. Please let me know if you need anything else to assist with this problem, happy to provide it ST2000DM006-2DM164_W4Z2XYVD-20190609-2316 disk2 (sdd).txt
June 9, 20197 yr Author It's very possible I didn't which probably means files are gone... Never felt so stupid not backing up the flash drive itself. I'll just have to recover whatever I can find from the backups I guess 🤷♂️
June 9, 20197 yr Set a new config, assign ALL your 2TB drives as data, no parity slot assignments at all. Start the array and see what happens. If you get 2 unmountable drives, stop the array, start in maintenance mode, and run file system checks on the 2 unmountable drives and copy the results here.
June 10, 20197 yr Community Expert 1 hour ago, BL4CK1EEE said: not backing up the flash drive For future, it's very easy to download a zipped backup of flash from Main - Boot Device - Flash - Flash Backup.
June 10, 20197 yr Author Just now, jonathanm said: file system checks By file system checks do you mean a SMART self test? If you are referring to a built-in diagnostics tool, where abouts will I find this? If so, see attached logs for DISK 1 and DISK 3 Just now, trurl said: For future, it's very easy to download a zipped backup of flash from Main - Boot Device - Flash - Flash Backup. Thanks mate - I'll have a look into this, is it possible to automate this? I did read in the doc's that its best to stop the array before making a backup of the config. ST2000DM001-1CH164_Z1E4L0GQ-20190609-1925.txt ST2000DM006-2DM164_W4Z2XYVD-20190609-1928.txt Edited June 10, 20197 yr by BL4CK1EEE Replied to trurl
June 10, 20197 yr 7 hours ago, BL4CK1EEE said: By file system checks do you mean a SMART self test? No. Click on the disk in the main tab, then click on the check button in the check filesystem status section.
June 10, 20197 yr Community Expert 8 hours ago, BL4CK1EEE said: is it possible to automate this https://forums.unraid.net/topic/61211-plugin-ca-appdata-backup-restore-v2/
June 10, 20197 yr Community Expert 11 hours ago, trurl said: Are you sure you assigned the correct disk to parity? 11 hours ago, BL4CK1EEE said: It's very possible I didn't which probably means files are gone... If you don't know whether or not you assigned the correct disk to parity then the odds are 75% that you assigned the wrong disk to parity. If the disk you assigned to parity was one of your data disks, and you let it build parity with those assignments, then it will be impossible to recover any data from that disk you assigned to the parity slot. And the disk you assigned to slot2, which would have actually been the parity disk, will also have no recoverable data. But since you don't know, then there is a 25% chance that disk2 is just a corrupt data disk and maybe can be repaired as jonathanm suggests. My bet would be on the 75% though.
June 10, 20197 yr I agree with @trurl's odds of recovery, but I'm optimistic because there is a second scenario where you may have recoverable data, even if you botched the assignments and built parity. Assuming... 1. Parity was valid at the moment the server went down originally. 2. You were using a single parity drive, in the FIRST parity slot. 3. You haven't written or deleted anything on the rest of the data drives after you got the array running with a single unmountable disk and good parity. Given your description of events, I feel pretty good about 1 and 2, not so good about point 3. A single parity array is valid regardless of slot assignments, even the parity disk. So if no bits are changed, you should be able to recover the file system on the unmountable data drive. The amount of write activity with the array in the condition you put in the first thread post determines recoverability. Every write makes it less likely your data is recoverable.
June 10, 20197 yr Community Expert 1 hour ago, jonathanm said: I agree with @trurl's odds of recovery, but I'm optimistic because there is a second scenario where you may have recoverable data, even if you botched the assignments and built parity. Assuming... 1. Parity was valid at the moment the server went down originally. 2. You were using a single parity drive, in the FIRST parity slot. 3. You haven't written or deleted anything on the rest of the data drives after you got the array running with a single unmountable disk and good parity. Given your description of events, I feel pretty good about 1 and 2, not so good about point 3. A single parity array is valid regardless of slot assignments, even the parity disk. So if no bits are changed, you should be able to recover the file system on the unmountable data drive. The amount of write activity with the array in the condition you put in the first thread post determines recoverability. Every write makes it less likely your data is recoverable. Assuming the 75% scenario where a data disk was assigned to the parity slot, then disk2 was actually the parity disk and so contains no data to recover. In that scenario, the only way I can see that anything might be recovered is if parity wasn't built on the data disk that was assigned to the parity slot. And since he was starting from nothing assigned instead of going from a New Config, I'm not sure the option to not build parity is even available. The 25% scenario where he accidentally assigned the correct disk to parity is the only optimistic scenario. Actually, based on the evidence that the currently assigned disk2 is unmountable, I would say the odds are worse than 25% that he accidentally assigned the correct disk to parity.
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