[LU-14695] New OST not visible by MDTs. MGS problem or corrupt catalog llog?

Related — Mon, 27 Sep 2021 15:49:14 +0000

On our Oak filesystem, running 2.12.6, we have a problem with either the MGS or a corrupt catalog somewhere.

Active OSTs on this filesystem are from OST000c (12) to OST0137 (311). Today, we tried to add OST index 312 oak-OST0138. The new OST is visible from client, but not from MDTs: we have 6 MDTs (oak-MDT0000 to oak-MDT0005).

Full disclosure... older OSTs 0-11 were previously removed with the experimental command lctl del_ost from ~~LU-7668~~.

The server logs when I started the new OST are available in servers-logs.txt

What is weird is the following:

May 20 14:06:05 oak-md1-s2 kernel: Lustre: 108193:0:(obd_config.c:1641:class_config_llog_handler()) Skip config outside markers, (inst: 0000000000000000, uuid: , flags: 0x0)

and that it complains about other OSTs (not OST0138):

May 20 14:06:05 oak-md1-s2 kernel: LustreError: 108193:0:(genops.c:556:class_register_device()) oak-OST0134-osc-MDT0003: already exists, won't add
May 20 14:06:05 oak-md1-s2 kernel: LustreError: 108193:0:(obd_config.c:1835:class_config_llog_handler()) MGC10.0.2.51@o2ib5: cfg command failed: rc = -17
May 20 14:06:05 oak-md1-s2 kernel: Lustre:    cmd=cf001 0:oak-OST0134-osc-MDT0003  1:osp  2:oak-MDT0003-mdtlov_UUID  
May 20 14:06:05 oak-md1-s2 kernel: LustreError: 4061:0:(mgc_request.c:599:do_requeue()) failed processing log: -17
May 20 14:06:05 oak-md1-s2 kernel: Lustre:    cmd=cf001 0:oak-OST0134-osc-MDT0000  1:osp  2:oak-MDT0000-mdtlov_UUID  
May 20 14:06:07 oak-md2-s2 kernel: Lustre: 14846:0:(obd_config.c:1641:class_config_llog_handler()) Skip config outside markers, (inst: 0000000000000000, uuid: , flags: 0x0)
May 20 14:06:07 oak-md2-s2 kernel: LustreError: 14846:0:(genops.c:556:class_register_device()) oak-OST0136-osc-MDT0005: already exists, won't add
May 20 14:06:07 oak-md2-s2 kernel: LustreError: 14846:0:(obd_config.c:1835:class_config_llog_handler()) MGC10.0.2.51@o2ib5: cfg command failed: rc = -17
May 20 14:06:07 oak-md2-s2 kernel: Lustre:    cmd=cf001 0:oak-OST0136-osc-MDT0005  1:osp  2:oak-MDT0005-mdtlov_UUID  
May 20 14:06:07 oak-md2-s2 kernel: LustreError: 4291:0:(mgc_request.c:599:do_requeue()) failed processing log: -17

If I check the llog catalogs on the MGS, the new OST oak-OST0138 seems to have been added though:

Client catalog on MGS:

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-client | grep OST0138
- { index: 2716, event: attach, device: oak-OST0138-osc, type: osc, UUID: oak-clilov_UUID }
- { index: 2717, event: setup, device: oak-OST0138-osc, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 2719, event: add_conn, device: oak-OST0138-osc, node: 10.0.2.104@o2ib5 }
- { index: 2720, event: add_osc, device: oak-clilov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

MDS catalogs on MGS:

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0000 | grep OST0138
- { index: 2785, event: attach, device: oak-OST0138-osc-MDT0000, type: osc, UUID: oak-MDT0000-mdtlov_UUID }
- { index: 2786, event: setup, device: oak-OST0138-osc-MDT0000, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 2788, event: add_conn, device: oak-OST0138-osc-MDT0000, node: 10.0.2.104@o2ib5 }
- { index: 2789, event: add_osc, device: oak-MDT0000-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0001 | grep OST0138
- { index: 2930, event: attach, device: oak-OST0138-osc-MDT0001, type: osc, UUID: oak-MDT0001-mdtlov_UUID }
- { index: 2931, event: setup, device: oak-OST0138-osc-MDT0001, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 2933, event: add_conn, device: oak-OST0138-osc-MDT0001, node: 10.0.2.104@o2ib5 }
- { index: 2934, event: add_osc, device: oak-MDT0001-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0002 | grep OST0138
- { index: 3063, event: attach, device: oak-OST0138-osc-MDT0002, type: osc, UUID: oak-MDT0002-mdtlov_UUID }
- { index: 3064, event: setup, device: oak-OST0138-osc-MDT0002, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 3066, event: add_conn, device: oak-OST0138-osc-MDT0002, node: 10.0.2.104@o2ib5 }
- { index: 3067, event: add_osc, device: oak-MDT0002-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0003 | grep OST0138
- { index: 3079, event: attach, device: oak-OST0138-osc-MDT0003, type: osc, UUID: oak-MDT0003-mdtlov_UUID }
- { index: 3080, event: setup, device: oak-OST0138-osc-MDT0003, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 3082, event: add_conn, device: oak-OST0138-osc-MDT0003, node: 10.0.2.104@o2ib5 }
- { index: 3083, event: add_osc, device: oak-MDT0003-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0004 | grep OST0138
- { index: 3255, event: attach, device: oak-OST0138-osc-MDT0004, type: osc, UUID: oak-MDT0004-mdtlov_UUID }
- { index: 3256, event: setup, device: oak-OST0138-osc-MDT0004, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 3258, event: add_conn, device: oak-OST0138-osc-MDT0004, node: 10.0.2.104@o2ib5 }
- { index: 3259, event: add_osc, device: oak-MDT0004-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

[root@oak-md1-s1 ~]# lctl --device MGS llog_print oak-MDT0005 | grep OST0138
- { index: 3255, event: attach, device: oak-OST0138-osc-MDT0005, type: osc, UUID: oak-MDT0005-mdtlov_UUID }
- { index: 3256, event: setup, device: oak-OST0138-osc-MDT0005, UUID: oak-OST0138_UUID, node: 10.0.2.103@o2ib5 }
- { index: 3258, event: add_conn, device: oak-OST0138-osc-MDT0005, node: 10.0.2.104@o2ib5 }
- { index: 3259, event: add_osc, device: oak-MDT0005-mdtlov, ost: oak-OST0138_UUID, index: 312, gen: 1 }

However, this new OST is NOT visible from the MDTs:

[root@oak-md1-s2 CONFIGS]# llog_reader /mnt/ldiskfs/mdt/0/CONFIGS/oak-MDT0000 | grep 0138
[root@oak-md1-s2 CONFIGS]# 

[root@oak-md1-s2 ~]# lctl dl | grep OST0138
[root@oak-md1-s2 ~]#

From a client, we can see the new OST but it's not filling up, which makes sense if the MDTs are not aware of it:

oak-OST0133_UUID     108461852548 37418203104 69949699416  35% /oak[OST:307]
oak-OST0134_UUID     108461852548 38597230784 68770659804  36% /oak[OST:308]
oak-OST0135_UUID     108461852548 38483562644 68884328272  36% /oak[OST:309]
oak-OST0136_UUID     108461852548 41312045604 66055819468  39% /oak[OST:310]
oak-OST0137_UUID     108461852548 43196874132 64170973596  41% /oak[OST:311]
oak-OST0138_UUID     108461852548        1828 107368054308   1% /oak[OST:312]

Right now, we're up and running in that weird situation... not ideal.

I'm attaching the catalogs found on the 6 MDTs as oak-MDT-CONFIGS-llog.tar and a tarball of the CONFIGS directory on the MGS as oak-MGS-CONFIGS.tar.gz

Any idea of what is wrong or corrupt? We would really appreciate any help to avoid doing a full writeconf.

Whamcloud Community JIRA

[LU-14695] New OST not visible by MDTs. MGS problem or corrupt catalog llog?