On 3/23/23 5:45 AM, Johnatan Hallman wrote: > Hello List, > > I get this error when I try to mount an XFS partition. > Fortunately there is no critical data on it as it is just a backup but I would still like to mount it if it's possible. > > I have tried with various Linux distros with kernels ranging from 5.6 to 6.1 it's the same result. > > xfs_info /dev/mapper/test > meta-data=/dev/mapper/test isize=256 agcount=32, agsize=30523559 blks > = sectsz=512 attr=2, projid32bit=0 > = crc=0 finobt=0, sparse=0, rmapbt=0 > = reflink=0 bigtime=0 inobtcount=0 nrext64=0 > data = bsize=4096 blocks=976753869, imaxpct=5 > = sunit=0 swidth=0 blks > naming =version 2 bsize=4096 ascii-ci=0, ftype=0 > log =internal log bsize=4096 blocks=476930, version=2 > = sectsz=512 sunit=0 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > mount -t xfs -o ro /dev/mapper/test /mnt/ > mount: /mnt: mount(2) system call failed: Function not implemented. > dmesg(1) may have more information after failed mount system call. So I assume dmesg contained the error in $SUBJECT: FS (dm-0): device supports 4096 byte sectors (not 512) It seems that the filesystem was created with 512-byte sectors - at that time, the device must have supported them. Perhaps something about the devicemapper target changed from a 512 device to a 4k device? I'm not sure what might cause that to happen, but IMHO it should never happen... did the dm device recently get reconfigured? As a last resort, I think you could dd the filesystem (all 3T) to a file, and use a loopback mount to access the files. Alternatively, I wonder if we could relax the sector size check for a read-only mount (that does not require log replay) - I'm not sure about that though. -Eric
