All OSSs and MDS are 1.8.3 CentOS x_86_64 Clients are a mix of 1.6.4.2, 1.8.1.1 and 1.8.3 Just hit an LBUG on our MDS. I googled it and searched lustre''s bugzilla without any luck: May 15 14:48:20 mds01 kernel: LustreError: 3867:0:(ldlm_lock.c:677:ldlm_lock_decref()) ASSERTION(lock != NULL) failed: Non-existing lock: 0x4a26a46afdc46bc6 May 15 14:48:20 mds01 kernel: LustreError: 3867:0:(ldlm_lock.c:677:ldlm_lock_decref()) LBUG May 15 14:48:20 mds01 kernel: Lustre: 3867:0:(linux-debug.c:264:libcfs_debug_dumpstack()) showing stack for process 3867 May 15 14:48:20 mds01 kernel: ll_mdt_55 R running task 0 3867 1 3868 3866 (L-TLB) May 15 14:48:20 mds01 kernel: ffff8100763d2d00 ffffffff80062ff8 ffff810062b8c000 0000000000000082 May 15 14:48:20 mds01 kernel: 0000008100001400 000000000000000a ffff81005be14820 ffff81007fa7c100 May 15 14:48:20 mds01 kernel: 0000000000000286 ffffffff8003dafe ffff81005bb5a4c0 ffff81007fa78000 May 15 14:48:20 mds01 kernel: Call Trace: May 15 14:48:20 mds01 kernel: [<ffffffff80062ff8>] thread_return+0x62/0xfe May 15 14:48:20 mds01 kernel: [<ffffffff8003dafe>] lock_timer_base+0x1b/0x3c May 15 14:48:20 mds01 kernel: [<ffffffff8001ca74>] __mod_timer+0xb0/0xbe May 15 14:48:20 mds01 kernel: [<ffffffff8861e408>] :ptlrpc:ptlrpc_main+0x1258/0x1420 May 15 14:48:20 mds01 kernel: [<ffffffff8008c86b>] default_wake_function+0x0/0xe May 15 14:48:20 mds01 kernel: [<ffffffff800b7076>] audit_syscall_exit+0x336/0x362 May 15 14:48:20 mds01 kernel: [<ffffffff8005dfb1>] child_rip+0xa/0x11 May 15 14:48:20 mds01 kernel: [<ffffffff8861d1b0>] :ptlrpc:ptlrpc_main+0x0/0x1420 May 15 14:48:20 mds01 kernel: [<ffffffff8005dfa7>] child_rip+0x0/0x11 May 15 14:48:20 mds01 kernel: May 15 14:48:20 mds01 kernel: LustreError: dumping log to /tmp/lustre-log.1273960100.3867 It looks like /tmp/lustre-log.1273960100.3867 has a whole bunch of messages like: pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0021_UUID (in recovery: DISCONN or recovery disabled: 1/0) pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0022_UUID (in recovery: DISCONN or recovery disabled: 1/0) pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0023_UUID (in recovery: DISCONN or recovery disabled: 1/0) pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0024_UUID (in recovery: DISCONN or recovery disabled: 1/0) pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0025_UUID (in recovery: DISCONN or recovery disabled: 1/0) pinger.c^@ptlrpc_pinger_main^@not pinging sanvol06-OST0026_UUID (in recovery: DISCONN or recovery disabled: 1/0) sanvol06-OST0021_UUID through sanvol06-OST0026_UUID are old OSTs that I removed many months ago and no longer exist. (All marked as lctl conf_param sanvol06-OST00xx.osc.active=0) I can access the volume just fine and don''t see any other issues. Thoughts? Thanks, Scott Barber Senior Systems Administrator iMemories.com