Hello, the problem has been resolved by mounting the mdt partition via ldiskfs and moving the .lustre directory back to the right place. So long! paul On Mon, Apr 22, 2013 at 3:37 PM, Paul Unger <paul.unger78(a)gmail.com&gt; wrote:

Hi, current Lustre release: 2.1.5 recently upgraded from 2.1.3 OS: Rhel5 (server), Rhel6 (clients), [...] the /mountpoint/.lustre (fsname=test) directory has been accidentally moved to a different place on a Lustre client with Lustre mounted. Later on, I rebooted the system and tried to mount the mdt (fsname=test) on the mds again, which wasn't possible anymore. The mgs and other mdt's on the same system were still fully operational. 1st I tried to regenerate the Lustre configuration logs, with no luck... 2nd The solution was to mount the mdt (fsname=test) via -t ldiskfs on the mds. mount -t ldiskfs /dev/dm-4 /mnt/MDT4 now, I changed to the ROOT directory and moved the .lustre directory back in place [root@xxx ROOT]# pwd /mnt/MDT4/ROOT [root@xxx ROOT]# ls -al total 20 drwxr-xr-x 5 root root 4096 Apr 22 16:24 . drwxr-xr-x 8 root root 4096 Jan 27 12:19 .. drwxr-xr-x 2 root root 4096 Jan 27 12:19 .lustre drwxr-xr-x 2 root root 4096 Apr 22 16:24 nobackup [root@xxx ROOT]# It solved the problem and I was able to mount the mdt (fsname=test) with the -t lustre option again. So long! Paul ~ ~ ~ On Mon, Apr 22, 2013 at 6:52 PM, Dilger, Andreas <andreas.dilger(a)intel.com&gt;wrote: