After upgrading a CentOS MGS/MDS server running zfs lustre from lustre: 2.3.64 kernel: patchless_client build: v2_3_64-1dkms-1-PRISTINE-2.6.32-358.2.1.el6.netboot to lustre: 2.5.57 kernel: patchless_client build: 2.5.57-g3423b5b-CHANGED-2.6.32-431.11.2.el6.netboot the MDT fails to mount with the messages below. "/sbin/service lustre start mgsmdt" brings the zpool online: NAME USED AVAIL REFER MOUNTPOINT lustre-mgs-mdt 47.2G 26.2G 30K /lustre-mgs-mdt lustre-mgs-mdt/mgsmdt0 46.5G 26.2G 27.8G /lustre-mgs-mdt/mgsmdt0 "lctl list_nids" shows 10.10.101.160@o2ib 128.182.75.160@tcp10 Any suggestions on how to get MDT to mount? Thanks, -Anjana Kar Pittsburgh Supercomputing Center kar-YUCGctl3KYs@public.gmane.org ------------------------------------------------------------------------------------------------------------------- 2014-04-21T13:05:03.641223-04:00 icon0.psc.edu kernel: SPL: using hostid 0xb680a04b LustreError: 11-0: iconfs-MDT0000-lwp-MDT0000: Communicating with 0@lo, operation mds_connect failed with -11. 2014-04-21T13:05:06.820694-04:00 icon0.psc.edu kernel: LustreError: 11-0: iconfs-MDT0000-lwp-MDT0000: Communicating with 0@lo, operation mds_connect failed with -11. LustreError: 3537:0:(mdd_device.c:1050:mdd_prepare()) iconfs-MDD0000: failed to initialize lfsck: rc = -17 LustreError: 3537:0:(obd_mount_server.c:1776:server_fill_super()) Unable to start targets: -17 2014-04-21T13:05Lustre: Failing over iconfs-MDT0000 :09.821666-04:00 icon0.psc.edu kernel: LustreError: 3537:0:(mdd_device.c:1050:mdd_prepare()) iconfs-MDD0000: failed to initialize lfsck: rc = -17 2014-04-21T13:05:09.821688-04:00 icon0.psc.edu kernel: LustreError: 3537:0:(obd_mount_server.c:1776:server_fill_super()) Unable to start targets: -17 2014-04-21T13:05:09.834743-04:00 icon0.psc.edu kernel: Lustre: Failing over iconfs-MDT0000