Hello Everyone, I am running a 2 node debian cluster (OCFS2, DRBD, pacmaker). When I issue an ifdown eth0 on one of the nodes, I got the following: [ 4772.359815] ------------[ cut here ]------------ [ 4772.359815] kernel BUG at /tmp/buildd/linux-2.6-2.6.32/debian/build/source_i386_none/fs/ocfs2/journal.c:1702! [ 4772.359815] invalid opcode: 0000 [#1] SMP [ 4772.359815] last sysfs file: /sys/fs/o2cb/interface_revision [ 4772.359815] Modules linked in: ocfs2 jbd2 quota_tree ocfs2_stack_o2cb ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs drbd lru_cache cn loop joydev usbhid hid sg snd_intel8x0 sr_mod snd_ac97_codec cdrom ohci_hcd ac97_bus ehci_hcd snd_pcm snd_timer psmouse i2c_piix4 usbcore snd ata_generic soundcore parport_pc serio_raw pcspkr snd_page_alloc parport nls_base ac evdev vboxguest e1000 button i2c_core battery ata_piix ext3 jbd mbcache sd_mod crc_t10dif ahci libata thermal thermal_sys scsi_mod [ 4772.359815] [ 4772.359815] Pid: 2582, comm: ocfs2rec Tainted: G W (2.6.32-5-686 #1) VirtualBox [ 4772.359815] EIP: 0060:[<c84f147a>] EFLAGS: 00010246 CPU: 0 [ 4772.359815] EIP is at __ocfs2_recovery_thread+0x3af/0x146d [ocfs2] [ 4772.359815] EAX: 00000002 EBX: c5635000 ECX: 00000001 EDX: 00000001 [ 4772.359815] ESI: 00000001 EDI: c1e592b0 EBP: 00000000 ESP: c5b77ed4 [ 4772.359815] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 4772.359815] Process ocfs2rec (pid: 2582, ti=c5b76000 task=c54f5980 task.ti=c5b76000) [ 4772.359815] Stack: [ 4772.359815] c54f5980 c54f5980 c563509c 00000002 00000001 c5635000 c1e592b0 c1e592e0 [ 4772.359815] <0> 00000002 c768e063 c768e080 00000000 00000246 c768b248 c1805e20 00000000 [ 4772.359815] <0> c1f82aac 00000000 c5704c40 c5704c40 c1413c48 00000000 c767198b c76719a8 [ 4772.359815] Call Trace: [ 4772.359815] [<c126d21e>] ? schedule+0x78f/0x7dc [ 4772.359815] [<c84f10cb>] ? __ocfs2_recovery_thread+0x0/0x146d [ocfs2] [ 4772.359815] [<c1043dec>] ? kthread+0x61/0x66 [ 4772.359815] [<c1043d8b>] ? kthread+0x0/0x66 [ 4772.359815] [<c1003d47>] ? kernel_thread_helper+0x7/0x10 [ 4772.359815] Code: 00 00 68 24 f7 52 c8 50 ff b2 2c 01 00 00 68 29 85 53 c8 e8 b4 b4 d7 f8 83 c4 20 8b 5c 24 14 8b 44 24 0c 39 83 bc 00 00 00 75 04 <0f> 0b eb fe 8d 84 24 d0 00 00 00 c7 84 24 d0 00 00 00 00 00 00 [ 4772.359815] EIP: [<c84f147a>] __ocfs2_recovery_thread+0x3af/0x146d [ocfs2] SS:ESP 0068:c5b77ed4 [ 4772.363813] ---[ end trace a7919e7f17c0a727 ]--- [ 4776.325831] (1704,0):dlm_get_lock_resource:839 3A791AB36DED41008E58CEF52EBEEFD3:$RECOVERY: at least one node (1) to recover before lock mastery can begin [ 4776.325831] (1704,0):dlm_get_lock_resource:873 3A791AB36DED41008E58CEF52EBEEFD3: recovery map is not empty, but must master $RECOVERY lock now [ 4776.325831] (1704,0):dlm_do_recovery:523 (1704) Node 2 is the Recovery Master for the Dead Node 1 for Domain 3A791AB36DED41008E58CEF52EBEEFD3 Thanks in advance, Nick.