[Ocfs2-devel] OCFS2 causing system instability

Junxiao Bi
Wed, 20 Jan 2016 08:51:00 -0000

Hi Guy,

ocfs2 is shared-disk fs, there is no way to do replication like dfs,
also no volume manager integrated in ocfs2. Ocfs2 depends on underlying
storage stack to handler disk failure, so you can configure multipath,
raid or storage to handle removing disk issue. If io error is still
reported to ocfs2, then there is no way to workaround, ocfs2 will be set
read-only or even panic to avoid fs corruption. This is the same
behavior with local fs.
If io error not reported to ocfs2, then there is a fix i just posted to
ocfs2-devel to avoid the node panic, please try patch serial [ocfs2:
o2hb: not fence self if storage down]. Note this is only useful to o2cb
stack. Nodes will hung on io and wait storage online again.

For the endless loop you met in "Appendix A1", it is a bug and fixed
by
"[PATCH V2] ocfs2: call ocfs2_abort when journal abort", you can get
it
from ocfs2-devel. This patch will set fs readonly or panic node since io
error have been reported to ocfs2.

Thanks,
Junxiao.

On 01/20/2016 03:19 AM, Guy 1234 wrote:
> 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
> <http://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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