Is it a plausible configuration?
Would you please tell me if this configuration is doable or there is something that i am missing? I would like to use only two servers (X and Y) for VDI and Gluster based storage. Hosted engine for oVirt and replicated volumes between X and Y for the gluster storage. Is a third machine Z a must?
----- Original Message -----
From: "Kiril L" <neohidra@gmail.com> To: users@ovirt.org Sent: Wednesday, June 3, 2015 3:32:52 PM Subject: [ovirt-users] Is it a plausible configuration?
Would you please tell me if this configuration is doable or there is something that i am missing?
I would like to use only two servers (X and Y) for VDI and Gluster based storage. Hosted engine for oVirt and replicated volumes between X and Y for the gluster storage. Is a third machine Z a must?
It works also with just two hosts but it's not that safe: a replica-2 GlusterFS volume affected by a split-brain issue could be not self-healing while with replica-3 you could rely on quorum enforcement just cause you are using an odd host number. For oVirt 3.6 we are working on http://www.ovirt.org/Features/Self_Hosted_Engine_Hyper_Converged_Gluster_Sup...
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Hi, Pardon me for jumping in subj, but... Could you explain me in a few words or give a link where to read about "split-brain"? I made a lab: cluster (virt and gluster services both) based on two server. With this options: cluster.server-quorum-type none cluster.quorum-type fixed cluster.quorum-count 1 I get a cluster that worked just fine even with only one host alive. I have run VM on a not SPM host B, have made some files, then on the SPM host A have stoped network service (host has gone, no power management), have made some huge files on the VM again, after that I have rebooted manualy the host A and there was no unexpected result. VM have worked without problem, I have rebooted the VM several times and there were no problems with any files I have made before. I want to build a cluster with only two hosts, because I have only two good servers free, and only 8x3TB HDD (for RAID10 in each host). To get one more server and 4HDD is unbelievable in a close future.. Thanks. 2015-06-03 16:54 GMT+03:00 Simone Tiraboschi <stirabos@redhat.com>:
----- Original Message -----
From: "Kiril L" <neohidra@gmail.com> To: users@ovirt.org Sent: Wednesday, June 3, 2015 3:32:52 PM Subject: [ovirt-users] Is it a plausible configuration?
Would you please tell me if this configuration is doable or there is something that i am missing?
I would like to use only two servers (X and Y) for VDI and Gluster based storage. Hosted engine for oVirt and replicated volumes between X and Y for the gluster storage. Is a third machine Z a must?
It works also with just two hosts but it's not that safe: a replica-2 GlusterFS volume affected by a split-brain issue could be not self-healing while with replica-3 you could rely on quorum enforcement just cause you are using an odd host number.
For oVirt 3.6 we are working on http://www.ovirt.org/Features/Self_Hosted_Engine_Hyper_Converged_Gluster_Sup...
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
This should clear things up a bit - https://joejulian.name/blog/glusterfs-split-brain-recovery-made-easy/ even On Thu, Jun 4, 2015 at 9:40 AM, Юрий Полторацкий <y.poltoratskiy@gmail.com> wrote:
Hi,
Pardon me for jumping in subj, but...
Could you explain me in a few words or give a link where to read about "split-brain"?
I made a lab: cluster (virt and gluster services both) based on two server. With this options: cluster.server-quorum-type none cluster.quorum-type fixed cluster.quorum-count 1 I get a cluster that worked just fine even with only one host alive.
I have run VM on a not SPM host B, have made some files, then on the SPM host A have stoped network service (host has gone, no power management), have made some huge files on the VM again, after that I have rebooted manualy the host A and there was no unexpected result. VM have worked without problem, I have rebooted the VM several times and there were no problems with any files I have made before.
I want to build a cluster with only two hosts, because I have only two good servers free, and only 8x3TB HDD (for RAID10 in each host). To get one more server and 4HDD is unbelievable in a close future..
Thanks.
2015-06-03 16:54 GMT+03:00 Simone Tiraboschi <stirabos@redhat.com>:
----- Original Message -----
From: "Kiril L" <neohidra@gmail.com> To: users@ovirt.org Sent: Wednesday, June 3, 2015 3:32:52 PM Subject: [ovirt-users] Is it a plausible configuration?
Would you please tell me if this configuration is doable or there is something that i am missing?
I would like to use only two servers (X and Y) for VDI and Gluster based storage. Hosted engine for oVirt and replicated volumes between X and Y for the gluster storage. Is a third machine Z a must?
It works also with just two hosts but it's not that safe: a replica-2 GlusterFS volume affected by a split-brain issue could be not self-healing while with replica-3 you could rely on quorum enforcement just cause you are using an odd host number.
For oVirt 3.6 we are working on http://www.ovirt.org/Features/Self_Hosted_Engine_Hyper_Converged_Gluster_Sup...
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
----- Original Message -----
From: "Kiril L" <neohidra@gmail.com> To: users@ovirt.org Sent: Wednesday, June 3, 2015 4:32:52 PM Subject: [ovirt-users] Is it a plausible configuration?
Would you please tell me if this configuration is doable or there is something that i am missing?
I would like to use only two servers (X and Y) for VDI and Gluster based storage. Hosted engine for oVirt and replicated volumes between X and Y for the gluster storage. Is a third machine Z a must?
Without that, you risk a split brain. In 3.6, what you want to do will be supported "out of the box" [1], but will require 3 hosts [2]. [1] http://www.ovirt.org/Features/Self_Hosted_Engine_Hyper_Converged_Gluster_Sup... [2] http://www.ovirt.org/Features/Self_Hosted_Engine_Gluster_Support#GlusterFS Best, -- Didi
participants (4)
-
Kiril L -
Simone Tiraboschi -
Yedidyah Bar David -
Юрий Полторацкий