Hello, I tried to reformat an OST and put it back into Lustre with a new name. However, now the clients are behaving in a weird way. The clients now seem to hang on df (takes about a minute to complete) Here's what I've done chronologically: 1. Deactivated the old OSTs [root@mds ~]# lctl dl 17 UP osp lustre-OST0004-osc-MDT0000 lustre-MDT0000-mdtlov_UUID 5 35 UP osp lustre-OST0005-osc-MDT0000 lustre-MDT0000-mdtlov_UUID 5 [root@mds ~]# lctl --device 17 deactivate [root@mds ~]# lctl --device 35 deactivate 2. Permanently disabled the old OSTs [root@mds ~]# lctl conf_param lustre-OST0004_UUID.osc.active=0 [root@mds ~]# lctl conf_param lustre-OST0005_UUID.osc.active=0 3. Reformatted the old OSTs into new OSTs with new names [root@oss19 ~]# umount /lustre/sdb [root@oss19 ~]# umount /lustre/sdc [root@oss19 ~]# mkfs.lustre --reformat --ost --mgsnode=192.168.0.1 --fsname=lustre --index=36 /dev/sdb [root@oss19 ~]# mkfs.lustre --reformat --ost --mgsnode=192.168.0.1 --fsname=lustre --index=37 /dev/sdc [root@oss19 ~]# mount /lustre/sdb [root@oss19 ~]# mount /lustre/sdc After these were done, I'm getting a lot of messages on the clients, while they hang on df: Jul 30 10:40:47 client kernel: LustreError: 11-0: lustre-OST0004-osc-ffff8804384d5c00: Communicating with 192.168.0.19@tcp, operation ost_connect failed with -19. Jul 30 10:40:47 client kernel: LustreError: Skipped 49 previous similar messages Jul 30 10:51:12 client kernel: LustreError: 11-0: lustre-OST0005-osc-ffff8804384d5c00: Communicating with 192.168.0.19@tcp, operation ost_connect failed with -19. Jul 30 10:51:12 client kernel: LustreError: Skipped 49 previous similar messages A workaround would be by marking the old OSTs as active on the clients, then mark as inactive again (this does not persist through reboots) [root@client ~]$ lctl set_param osc.lustre-OST0004-*.active=1 [root@client ~]$ lctl set_param osc.lustre-OST0005-*.active=1 [root@client ~]$ lctl set_param osc.lustre-OST0004-*.active=0 [root@client ~]$ lctl set_param osc.lustre-OST0005-*.active=0 Looking at this issue, I think a writeconf is required on all servers and clients http://wiki.lustre.org/manual/LustreManual20_HTML/LustreMaintenance.html#50438199_54623. Do you foresee any problems running this on our production system? I'm running Lustre 2.5.0 on servers and clients. Thanks, Murshid Azman. _______________________________________________ Lustre-discuss mailing list Lustre-discuss-aLEFhgZF4x6X6Mz3xDxJMA@public.gmane.org http://lists.lustre.org/mailman/listinfo/lustre-discuss