Wednesday, July 10, 2019, 4:26:14 PM, you wrote: > On 7/10/19 4:56 AM, Andrey Zhunev wrote: >> Hello All, >> >> I am struggling to recover my system after a PSU failure, and I was >> suggested to ask here for support. >> >> One of the hard drives throws some read errors, and that happen to be >> my root drive... >> My system is CentOS 7, and the root partition is a part of LVM. >> >> [root@mgmt ~]# lvscan >> ACTIVE '/dev/centos/root' [<98.83 GiB] inherit >> ACTIVE '/dev/centos/home' [<638.31 GiB] inherit >> ACTIVE '/dev/centos/swap' [<7.52 GiB] inherit >> [root@mgmt ~]# >> >> [root@tftp ~]# file -s /dev/centos/root >> /dev/centos/root: symbolic link to `../dm-3' >> [root@tftp ~]# file -s /dev/centos/home >> /dev/centos/home: symbolic link to `../dm-4' >> [root@tftp ~]# file -s /dev/dm-3 >> /dev/dm-3: SGI XFS filesystem data (blksz 4096, inosz 256, v2 dirs) >> [root@tftp ~]# file -s /dev/dm-4 >> /dev/dm-4: SGI XFS filesystem data (blksz 4096, inosz 256, v2 dirs) >> >> >> [root@tftp ~]# xfs_repair /dev/centos/root >> Phase 1 - find and verify superblock... >> superblock read failed, offset 53057945600, size 131072, ag 2, rval -1 >> >> fatal error -- Input/output error > look at dmesg, see what the kernel says about the read failure. > You might be able to use https://www.gnu.org/software/ddrescue/ > to read as many sectors off the device into an image file as possible, > and that image might be enough to work with for recovery. That would be > my first approach: > 1) use dd-rescue to create an image file of the device > 2) make a copy of that image file > 3) run xfs_repair -n on the copy to see what it would do > 4) if that looks reasonable run xfs_repair on the copy > 5) mount the copy and see what you get > But if your drive simply cannot be read at all, this is not a filesystem > problem, it is a hardware problem. If this is critical data you may wish > to hire a data recovery service. > -Eric Hi Eric, Thanks for your message! I already started to copy the failing drive with ddrescue. This is a large drive, so it takes some time to complete... When I tried to run xfs_repair on the original (failing) drive, the xfs_repair was unable to read the superblock and then just quitted with an 'io error'. Do you think it can behave differently on a copied image ? I will definitely give it a try once the ddrescue finishes. P.S. The data on this drive is not THAT critical to hire a professional data recovery service. Still, there are some files I would really like to restore (mostly settings and configuration files - nothing large, but important)... This will save me weeks to reconfigure and get the system back to its original state... Backups, always make backups... yeah, I know... :( --- Best regards, Andrey
