[Gluster-users] RE : Frequent connect and disconnect messages flooded in logs

Micha Ober micha2k at gmail.com
Tue Dec 6 23:32:53 UTC 2016


Hi,

thank you for your answer and even more for the question!
Until now, I was using FUSE. Today I changed all mounts to NFS using the 
same 3.7.17 version.

But: The problem is still the same. Now, the NFS logfile contains lines 
like these:

[2016-12-06 15:12:29.006325] C 
[rpc-clnt-ping.c:165:rpc_clnt_ping_timer_expired] 0-gv0-client-7: server 
X.X.18.62:49153 has not responded in the last 42 seconds, disconnecting.

Interestingly enough,  the IP address X.X.18.62 is the same machine! As 
I wrote earlier, each node serves both as a server and a client, as each 
node contributes bricks to the volume. Every server is connecting to 
itself via its hostname. For example, the fstab on the node "giant2" 
looks like:

#giant2:/gv0    /shared_data    glusterfs       defaults,noauto 0       0
#giant2:/gv2    /shared_slurm   glusterfs       defaults,noauto 0       0

giant2:/gv0     /shared_data    nfs defaults,_netdev,vers=3 0       0
giant2:/gv2     /shared_slurm   nfs defaults,_netdev,vers=3 0       0

So I understand the disconnects even less.

I don't know if it's possible to create a dummy cluster which exposes 
the same behaviour, because the disconnects only happen when there are 
compute jobs running on those nodes - and they are GPU compute jobs, so 
that's something which cannot be easily emulated in a VM.

As we have more clusters (which are running fine with an ancient 3.4 
version :-)) and we are currently not dependent on this particular 
cluster (which may stay like this for this month, I think) I should be 
able to deploy the debug build on the "real" cluster, if you can provide 
a debug build.

Regards and thanks,
Micha



Am 06.12.2016 um 08:15 schrieb Mohammed Rafi K C:
>
>
>
> On 12/03/2016 12:56 AM, Micha Ober wrote:
>> ** Update: ** I have downgraded from 3.8.6 to 3.7.17 now, but the 
>> problem still exists.
>>
>> Client log: http://paste.ubuntu.com/23569065/
>> Brick log: http://paste.ubuntu.com/23569067/
>>
>> Please note that each server has two bricks.
>> Whereas, according to the logs, one brick loses the connection to all 
>> other hosts:
>> [2016-12-02 18:38:53.703301] W [socket.c:596:__socket_rwv] 0-tcp.gv0-server: writev on X.X.X.219:49121 failed (Broken pipe)
>> [2016-12-02 18:38:53.703381] W [socket.c:596:__socket_rwv] 0-tcp.gv0-server: writev on X.X.X.62:49118 failed (Broken pipe)
>> [2016-12-02 18:38:53.703380] W [socket.c:596:__socket_rwv] 0-tcp.gv0-server: writev on X.X.X.107:49121 failed (Broken pipe)
>> [2016-12-02 18:38:53.703424] W [socket.c:596:__socket_rwv] 0-tcp.gv0-server: writev on X.X.X.206:49120 failed (Broken pipe)
>> [2016-12-02 18:38:53.703359] W [socket.c:596:__socket_rwv] 0-tcp.gv0-server: writev on X.X.X.58:49121 failed (Broken pipe)
>>
>> The SECOND brick on the SAME host is NOT affected, i.e. no disconnects!
>> As I said, the network connection is fine and the disks are idle.
>> The CPU always has 2 free cores.
>>
>> It looks like I have to downgrade to 3.4 now in order for the disconnects to stop.
>
> Hi Micha,
>
> Thanks for the update and sorry for what happened with gluster higher 
> versions. I can understand the need for downgrade as it is a 
> production setup.
>
> Can you tell me the clients used here ? whether it is a 
> fuse,nfs,nfs-ganesha, smb or libgfapi ?
>
> Since I'm not able to reproduce the issue (I have been trying from 
> last 3days) and the logs are not much helpful here (we don't have much 
> logs in socket layer), Could you please create a dummy cluster and try 
> to reproduce the issue? If then we can play with that volume and I 
> could provide some debug build which we can use for further debugging?
>
> If you don't have bandwidth for this, please leave it ;).
>
> Regards
> Rafi KC
>
>> - Micha
>>
>> Am 30.11.2016 um 06:57 schrieb Mohammed Rafi K C:
>>>
>>> Hi Micha,
>>>
>>> I have changed the thread and subject so that your original thread 
>>> remain same for your query. Let's try to fix the problem what you 
>>> observed with 3.8.4, So I have started a new thread to discuss the 
>>> frequent disconnect problem.
>>>
>>> *If any one else has experienced the same problem, please respond to 
>>> the mail.*
>>>
>>> It would be very helpful if you could give us some more logs from 
>>> clients and bricks.  Also any reproducible steps will surely help to 
>>> chase the problem further.
>>>
>>> Regards
>>>
>>> Rafi KC
>>>
>>> On 11/30/2016 04:44 AM, Micha Ober wrote:
>>>> I had opened another thread on this mailing list (Subject: "After 
>>>> upgrade from 3.4.2 to 3.8.5 - High CPU usage resulting in 
>>>> disconnects and split-brain").
>>>>
>>>> The title may be a bit misleading now, as I am no longer observing 
>>>> high CPU usage after upgrading to 3.8.6, but the disconnects are 
>>>> still happening and the number of files in split-brain is growing.
>>>>
>>>> Setup: 6 compute nodes, each serving as a glusterfs server and 
>>>> client, Ubuntu 14.04, two bricks per node, distribute-replicate
>>>>
>>>> I have two gluster volumes set up (one for scratch data, one for 
>>>> the slurm scheduler). Only the scratch data volume shows critical 
>>>> errors "[...] has not responded in the last 42 seconds, 
>>>> disconnecting.". So I can rule out network problems, the gigabit 
>>>> link between the nodes is not saturated at all. The disks are 
>>>> almost idle (<10%).
>>>>
>>>> I have glusterfs 3.4.2 on Ubuntu 12.04 on a another compute 
>>>> cluster, running fine since it was deployed.
>>>> I had glusterfs 3.4.2 on Ubuntu 14.04 on this cluster, running fine 
>>>> for almost a year.
>>>>
>>>> After upgrading to 3.8.5, the problems (as described) started. I 
>>>> would like to use some of the new features of the newer versions 
>>>> (like bitrot), but the users can't run their compute jobs right now 
>>>> because the result files are garbled.
>>>>
>>>> There also seems to be a bug report with a smiliar problem: (but no 
>>>> progress)
>>>> https://bugzilla.redhat.com/show_bug.cgi?id=1370683
>>>>
>>>> For me, ALL servers are affected (not isolated to one or two servers)
>>>>
>>>> I also see messages like "INFO: task gpu_graphene_bv:4476 blocked 
>>>> for more than 120 seconds." in the syslog.
>>>>
>>>> For completeness (gv0 is the scratch volume, gv2 the slurm volume):
>>>>
>>>> [root at giant2: ~]# gluster v info
>>>>
>>>> Volume Name: gv0
>>>> Type: Distributed-Replicate
>>>> Volume ID: 993ec7c9-e4bc-44d0-b7c4-2d977e622e86
>>>> Status: Started
>>>> Snapshot Count: 0
>>>> Number of Bricks: 6 x 2 = 12
>>>> Transport-type: tcp
>>>> Bricks:
>>>> Brick1: giant1:/gluster/sdc/gv0
>>>> Brick2: giant2:/gluster/sdc/gv0
>>>> Brick3: giant3:/gluster/sdc/gv0
>>>> Brick4: giant4:/gluster/sdc/gv0
>>>> Brick5: giant5:/gluster/sdc/gv0
>>>> Brick6: giant6:/gluster/sdc/gv0
>>>> Brick7: giant1:/gluster/sdd/gv0
>>>> Brick8: giant2:/gluster/sdd/gv0
>>>> Brick9: giant3:/gluster/sdd/gv0
>>>> Brick10: giant4:/gluster/sdd/gv0
>>>> Brick11: giant5:/gluster/sdd/gv0
>>>> Brick12: giant6:/gluster/sdd/gv0
>>>> Options Reconfigured:
>>>> auth.allow: X.X.X.*,127.0.0.1
>>>> nfs.disable: on
>>>>
>>>> Volume Name: gv2
>>>> Type: Replicate
>>>> Volume ID: 30c78928-5f2c-4671-becc-8deaee1a7a8d
>>>> Status: Started
>>>> Snapshot Count: 0
>>>> Number of Bricks: 1 x 2 = 2
>>>> Transport-type: tcp
>>>> Bricks:
>>>> Brick1: giant1:/gluster/sdd/gv2
>>>> Brick2: giant2:/gluster/sdd/gv2
>>>> Options Reconfigured:
>>>> auth.allow: X.X.X.*,127.0.0.1
>>>> cluster.granular-entry-heal: on
>>>> cluster.locking-scheme: granular
>>>> nfs.disable: on
>>>>
>>>>
>>>> 2016-11-30 0:10 GMT+01:00 Micha Ober <micha2k at gmail.com 
>>>> <mailto:micha2k at gmail.com>>:
>>>>
>>>>     There also seems to be a bug report with a smiliar problem:
>>>>     (but no progress)
>>>>     https://bugzilla.redhat.com/show_bug.cgi?id=1370683
>>>>     <https://bugzilla.redhat.com/show_bug.cgi?id=1370683>
>>>>
>>>>     For me, ALL servers are affected (not isolated to one or two
>>>>     servers)
>>>>
>>>>     I also see messages like "INFO: task gpu_graphene_bv:4476
>>>>     blocked for more than 120 seconds." in the syslog.
>>>>
>>>>     For completeness (gv0 is the scratch volume, gv2 the slurm volume):
>>>>
>>>>     [root at giant2: ~]# gluster v info
>>>>
>>>>     Volume Name: gv0
>>>>     Type: Distributed-Replicate
>>>>     Volume ID: 993ec7c9-e4bc-44d0-b7c4-2d977e622e86
>>>>     Status: Started
>>>>     Snapshot Count: 0
>>>>     Number of Bricks: 6 x 2 = 12
>>>>     Transport-type: tcp
>>>>     Bricks:
>>>>     Brick1: giant1:/gluster/sdc/gv0
>>>>     Brick2: giant2:/gluster/sdc/gv0
>>>>     Brick3: giant3:/gluster/sdc/gv0
>>>>     Brick4: giant4:/gluster/sdc/gv0
>>>>     Brick5: giant5:/gluster/sdc/gv0
>>>>     Brick6: giant6:/gluster/sdc/gv0
>>>>     Brick7: giant1:/gluster/sdd/gv0
>>>>     Brick8: giant2:/gluster/sdd/gv0
>>>>     Brick9: giant3:/gluster/sdd/gv0
>>>>     Brick10: giant4:/gluster/sdd/gv0
>>>>     Brick11: giant5:/gluster/sdd/gv0
>>>>     Brick12: giant6:/gluster/sdd/gv0
>>>>     Options Reconfigured:
>>>>     auth.allow: X.X.X.*,127.0.0.1
>>>>     nfs.disable: on
>>>>
>>>>     Volume Name: gv2
>>>>     Type: Replicate
>>>>     Volume ID: 30c78928-5f2c-4671-becc-8deaee1a7a8d
>>>>     Status: Started
>>>>     Snapshot Count: 0
>>>>     Number of Bricks: 1 x 2 = 2
>>>>     Transport-type: tcp
>>>>     Bricks:
>>>>     Brick1: giant1:/gluster/sdd/gv2
>>>>     Brick2: giant2:/gluster/sdd/gv2
>>>>     Options Reconfigured:
>>>>     auth.allow: X.X.X.*,127.0.0.1
>>>>     cluster.granular-entry-heal: on
>>>>     cluster.locking-scheme: granular
>>>>     nfs.disable: on
>>>>
>>>>
>>>>     2016-11-29 19:21 GMT+01:00 Micha Ober <micha2k at gmail.com>:
>>>>
>>>>         I had opened another thread on this mailing list (Subject:
>>>>         "After upgrade from 3.4.2 to 3.8.5 - High CPU usage
>>>>         resulting in disconnects and split-brain").
>>>>
>>>>         The title may be a bit misleading now, as I am no longer
>>>>         observing high CPU usage after upgrading to 3.8.6, but the
>>>>         disconnects are still happening and the number of files in
>>>>         split-brain is growing.
>>>>
>>>>         Setup: 6 compute nodes, each serving as a glusterfs server
>>>>         and client, Ubuntu 14.04, two bricks per node,
>>>>         distribute-replicate
>>>>
>>>>         I have two gluster volumes set up (one for scratch data,
>>>>         one for the slurm scheduler). Only the scratch data volume
>>>>         shows critical errors "[...] has not responded in the last
>>>>         42 seconds, disconnecting.". So I can rule out network
>>>>         problems, the gigabit link between the nodes is not
>>>>         saturated at all. The disks are almost idle (<10%).
>>>>
>>>>         I have glusterfs 3.4.2 on Ubuntu 12.04 on a another compute
>>>>         cluster, running fine since it was deployed.
>>>>         I had glusterfs 3.4.2 on Ubuntu 14.04 on this cluster,
>>>>         running fine for almost a year.
>>>>
>>>>         After upgrading to 3.8.5, the problems (as described)
>>>>         started. I would like to use some of the new features of
>>>>         the newer versions (like bitrot), but the users can't run
>>>>         their compute jobs right now because the result files are
>>>>         garbled.
>>>>
>>>>         2016-11-29 18:53 GMT+01:00 Atin Mukherjee
>>>>         <amukherj at redhat.com>:
>>>>
>>>>             Would you be able to share what is not working for you
>>>>             in 3.8.x (mention the exact version). 3.4 is quite old
>>>>             and falling back to an unsupported version doesn't look
>>>>             a feasible option.
>>>>
>>>>             On Tue, 29 Nov 2016 at 17:01, Micha Ober
>>>>             <micha2k at gmail.com> wrote:
>>>>
>>>>                 Hi,
>>>>
>>>>                 I was using gluster 3.4 and upgraded to 3.8, but
>>>>                 that version showed to be unusable for me. I now
>>>>                 need to downgrade.
>>>>
>>>>                 I'm running Ubuntu 14.04. As upgrades of the op
>>>>                 version are irreversible, I guess I have to delete
>>>>                 all gluster volumes and re-create them with the
>>>>                 downgraded version.
>>>>
>>>>                 0. Backup data
>>>>                 1. Unmount all gluster volumes
>>>>                 2. apt-get purge glusterfs-server glusterfs-client
>>>>                 3. Remove PPA for 3.8
>>>>                 4. Add PPA for older version
>>>>                 5. apt-get install glusterfs-server glusterfs-client
>>>>                 6. Create volumes
>>>>
>>>>                 Is "purge" enough to delete all configuration files
>>>>                 of the currently installed version or do I need to
>>>>                  manually clear some residues before installing an
>>>>                 older version?
>>>>
>>>>                 Thanks.
>>>>                 _______________________________________________
>>>>                 Gluster-users mailing list
>>>>                 Gluster-users at gluster.org
>>>>                 <mailto:Gluster-users at gluster.org>
>>>>                 http://www.gluster.org/mailman/listinfo/gluster-users
>>>>                 <http://www.gluster.org/mailman/listinfo/gluster-users>
>>>>
>>>>             -- 
>>>>             - Atin (atinm)
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Gluster-users mailing list
>>>> Gluster-users at gluster.org
>>>> http://www.gluster.org/mailman/listinfo/gluster-users
>>>
>>
>

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