[Ocfs2-devel] OCFS2 causing system instability

Guy 1234
Tue, 19 Jan 2016 19:19:53 -0000

Dear OCFS2 guys,



My name is Guy, and I'm testing ocfs2 due to its features as a clustered
filesystem that I need.

As part of the stability and reliability test I?ve performed, I've
encountered an issue with ocfs2 (format + mount + remove disk...), that I
wanted to make sure it is a real issue and not just a mis-configuration.



The main concern is that the stability of the whole system is compromised
when a single disk/volumes fails. It looks like the OCFS2 is not handling
the error correctly but stuck in an endless loop that interferes with the
work of the server.



I?ve test tested two cluster configurations ? (1) Corosync/Pacemaker and
(2) o2cb that react similarly.

Following the process and log entries:


Also below additional configuration that were tested.


Node 1:

======
1. service corosync start

2. service dlm start

3. mkfs.ocfs2 -v -Jblock64 -b 4096 --fs-feature-level=max-features
--cluster-=pcmk --cluster-name=cluster-name -N 2 /dev/<path to device>

4. mount -o
rw,noatime,nodiratime,data=writeback,heartbeat=none,cluster_stack=pcmk
/dev/<path to device> /mnt/ocfs2-mountpoint



Node 2:

======
5. service corosync start

6. service dlm start

7. mount -o
rw,noatime,nodiratime,data=writeback,heartbeat=none,cluster_stack=pcmk
/dev/<path to device> /mnt/ocfs2-mountpoint



So far all is working well, including reading and writing.

Next

8. I?ve physically, pull out the disk at /dev/<path to device> to simulate
a hardware failure (that may occur?) , in real life the disk is (hardware
or software) protected. Nonetheless, I?m testing a hardware failure that
the one of the OCFS2 file systems in my server fails.

Following  - messages observed in the system log (see below) and

==>  9. kernel panic(!) ... in one of the nodes or on both, or reboot on
one of the nodes or both.


Is there any configuration or set of parameters that will enable the system
to continue working, disabling the access to the failed disk without
compromising the system stability and not cause the kernel to panic?!



>From my point of view it looks basics ? when a hardware failure occurs:

1. All remaining hardware should continue working

2. The failed disk/volume should be inaccessible ? but not compromise the
whole system availability (Kernel panic).

3. OCFS2 ?understands? there?s a failed disk and stop trying to access it.

3. All disk commands such as mount/umount, df etc. should continue working.

4. When a new/replacement drive is connected to the system, it can be
accessed.

My settings:

ubuntu 14.04

linux:  3.16.0-46-generic

mkfs.ocfs2 1.8.4 (downloaded from git)





Some other scenarios which also were tested:

1. Remove the max-features in the mkfs (i.e. mkfs.ocfs2 -v -Jblock64 -b
4096 --cluster-stack=pcmk --cluster-name=cluster-name -N 2 /dev/<path to
device>)

This improved in some of the cases with no kernel panic but still the
stability of the system was compromised, the syslog indicates that
something unrecoverable is going on (See below - Appendix A1). Furthermore,
System is hanging when trying to software reboot.

2. Also tried with the o2cb stack, with similar outcomes.

3. The configuration was also tested with (1,2 and 3) Local and Global
heartbeat(s) that were NOT on the simulated failed disk, but on other
physical disks.

4. Also tested:

Ubuntu 15.15

Kernel: 4.2.0-23-generic

mkfs.ocfs2 1.8.4 (git clone git://oss.oracle.com/git/ocfs2-tools.git)





=============
Appendix A1:

=============
from syslog:

[ 1676.608123] (ocfs2cmt,5316,14):ocfs2_commit_thread:2195 ERROR: status -5,
journal is already aborted.

[ 1677.611827] (ocfs2cmt,5316,14):ocfs2_commit_cache:324 ERROR: status = -5

[ 1678.616634] (ocfs2cmt,5316,15):ocfs2_commit_cache:324 ERROR: status = -5

[ 1679.621419] (ocfs2cmt,5316,15):ocfs2_commit_cache:324 ERROR: status = -5

[ 1680.626175] (ocfs2cmt,5316,15):ocfs2_commit_cache:324 ERROR: status = -5

[ 1681.630981] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1682.107356] INFO: task kworker/u64:0:6 blocked for more than 120 seconds.

[ 1682.108440]       Not tainted 3.16.0-46-generic #62~14.04.1

[ 1682.109388] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables
this message.

[ 1682.110381] kworker/u64:0   D ffff88103fcb30c0     0     6      2
0x00000000

[ 1682.110401] Workqueue: fw_event0 _firmware_event_work [mpt3sas]

[ 1682.110405]  ffff88102910b8a0 0000000000000046 ffff88102977b2f0
00000000000130c0

[ 1682.110411]  ffff88102910bfd8 00000000000130c0 ffff88102928c750
ffff88201db284b0

[ 1682.110415]  ffff88201db28000 ffff881028cef000 ffff88201db28138
ffff88201db28268

[ 1682.110419] Call Trace:

[ 1682.110427]  [<ffffffff8176a8b9>] schedule+0x29/0x70

[ 1682.110458]  [<ffffffffc08d6c11>] ocfs2_clear_inode+0x3b1/0xa30 [ocfs2]

[ 1682.110464]  [<ffffffff810b4de0>] ? prepare_to_wait_event+0x100/0x100

[ 1682.110487]  [<ffffffffc08d8c7e>] ocfs2_evict_inode+0x6e/0x730 [ocfs2]

[ 1682.110493]  [<ffffffff811eee04>] evict+0xb4/0x180

[ 1682.110498]  [<ffffffff811eef09>] dispose_list+0x39/0x50

[ 1682.110501]  [<ffffffff811efdb4>] invalidate_inodes+0x134/0x150

[ 1682.110506]  [<ffffffff8120a64a>] __invalidate_device+0x3a/0x60

[ 1682.110510]  [<ffffffff81367e81>] invalidate_partition+0x31/0x50

[ 1682.110513]  [<ffffffff81368f45>] del_gendisk+0xf5/0x290

[ 1682.110519]  [<ffffffff815177a1>] sd_remove+0x61/0xc0

[ 1682.110524]  [<ffffffff814baf7f>] __device_release_driver+0x7f/0xf0

[ 1682.110529]  [<ffffffff814bb013>] device_release_driver+0x23/0x30

[ 1682.110534]  [<ffffffff814ba918>] bus_remove_device+0x108/0x180

[ 1682.110538]  [<ffffffff814b7169>] device_del+0x129/0x1c0

[ 1682.110543]  [<ffffffff815123a5>] __scsi_remove_device+0xd5/0xe0

[ 1682.110547]  [<ffffffff815123d6>] scsi_remove_device+0x26/0x40

[ 1682.110551]  [<ffffffff81512590>] scsi_remove_target+0x170/0x230

[ 1682.110561]  [<ffffffffc03551e5>] sas_rphy_remove+0x65/0x80
[scsi_transport_sas]

[ 1682.110570]  [<ffffffffc035707d>] sas_port_delete+0x2d/0x170
[scsi_transport_sas]

[ 1682.110575]  [<ffffffff8124a6f9>] ? sysfs_remove_link+0x19/0x30

[ 1682.110588]  [<ffffffffc03f1599>]
mpt3sas_transport_port_remove+0x1c9/0x1e0 [mpt3sas]

[ 1682.110598]  [<ffffffffc03e60b5>] _scsih_remove_device+0x55/0x80
[mpt3sas]

[ 1682.110610]  [<ffffffffc03e6159>]
_scsih_device_remove_by_handle.part.21+0x79/0xa0 [mpt3sas]

[ 1682.110619]  [<ffffffffc03eca97>] _firmware_event_work+0x1337/0x1690
[mpt3sas]

[ 1682.110626]  [<ffffffff8101c315>] ? native_sched_clock+0x35/0x90

[ 1682.110630]  [<ffffffff8101c379>] ? sched_clock+0x9/0x10

[ 1682.110636]  [<ffffffff81011574>] ? __switch_to+0xe4/0x580

[ 1682.110640]  [<ffffffff81087bc9>] ? pwq_activate_delayed_work+0x39/0x80

[ 1682.110644]  [<ffffffff8108a302>] process_one_work+0x182/0x450

[ 1682.110648]  [<ffffffff8108aa71>] worker_thread+0x121/0x570

[ 1682.110652]  [<ffffffff8108a950>] ? rescuer_thread+0x380/0x380

[ 1682.110657]  [<ffffffff81091309>] kthread+0xc9/0xe0

[ 1682.110662]  [<ffffffff81091240>] ? kthread_create_on_node+0x1c0/0x1c0

[ 1682.110667]  [<ffffffff8176e818>] ret_from_fork+0x58/0x90

[ 1682.110672]  [<ffffffff81091240>] ? kthread_create_on_node+0x1c0/0x1c0

[ 1682.635761] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1683.640549] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1684.645336] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1685.650114] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1686.654911] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1687.659684] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1688.664466] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1689.669252] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1690.674026] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1691.678810] (ocfs2cmt,5316,9):ocfs2_commit_cache:324 ERROR: status = -5

[ 1691.679920] (ocfs2cmt,5316,9):ocfs2_commit_thread:2195 ERROR: status -5,
journal is already aborted.



Thanks in advance,

Guy
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