Ha cluster 3 nodes but 1 slow
------LR35WVKSJTP2ZE0S9J713PVY1DHYNC Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Hi Currently, i ve 3 nodes, 2 in same DC and a third in another DC. They are all bridged together through a vpn. I know a cluster is at least 3 nodes to satisfy the quorum. My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2. And use the slow third node to satisfy quorum and a gluster geo-replication to act as a Backup. Let me know if this is technically suitable with Ovirt. Thanks a lot Regards Nico ------LR35WVKSJTP2ZE0S9J713PVY1DHYNC Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit Hi<br> <br> Currently, i ve 3 nodes, 2 in same DC and a third in another DC. <br> <br> They are all bridged together through a vpn. <br> <br> I know a cluster is at least 3 nodes to satisfy the quorum. <br> <br> My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2.<br> <br> And use the slow third node to satisfy quorum and a gluster geo-replication to act as a Backup.<br> <br> Let me know if this is technically suitable with Ovirt.<br> <br> Thanks a lot <br> Regards <br> Nico ------LR35WVKSJTP2ZE0S9J713PVY1DHYNC--
Perhaps using https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volume... ? This has not been tested, AFAIK. Y. On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <gluster@distran.org> wrote:
Hi
Currently, i ve 3 nodes, 2 in same DC and a third in another DC.
They are all bridged together through a vpn.
I know a cluster is at least 3 nodes to satisfy the quorum.
My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2.
And use the slow third node to satisfy quorum and a gluster geo-replication to act as a Backup.
Let me know if this is technically suitable with Ovirt.
Thanks a lot Regards Nico _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <gluster@distran.org> wrote:
Hi
Currently, i ve 3 nodes, 2 in same DC and a third in another DC.
They are all bridged together through a vpn.
I know a cluster is at least 3 nodes to satisfy the quorum.
My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2.
gluster replica 2 is not supported. Nir
------M6FE3B9WI3I917IEZZJ7YA45LB4T6Q Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Hey Nil What about https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volume... ? Regards Nico Le 18 octobre 2015 15:12:23 GMT+02:00, Nir Soffer <nsoffer@redhat.com> a écrit :
On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <gluster@distran.org> wrote:
Hi
Currently, i ve 3 nodes, 2 in same DC and a third in another DC.
They are all bridged together through a vpn.
I know a cluster is at least 3 nodes to satisfy the quorum.
My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2.
gluster replica 2 is not supported.
Nir
------M6FE3B9WI3I917IEZZJ7YA45LB4T6Q Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit <html><head></head><body>Hey Nil <br> <br> What about <a href="https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volumes">https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volumes</a>/ ?<br> <br> Regards<br> Nico <br> <br><br><div class="gmail_quote">Le 18 octobre 2015 15:12:23 GMT+02:00, Nir Soffer <nsoffer@redhat.com> a écrit :<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <pre class="k9mail">On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <gluster@distran.org> wrote:<br /><blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> Hi<br /><br /> Currently, i ve 3 nodes, 2 in same DC and a third in another DC.<br /><br /> They are all bridged together through a vpn.<br /><br /> I know a cluster is at least 3 nodes to satisfy the quorum.<br /><br /> My question is to know if i can have my VM balancing on the 2 fast nodes<br /> with HA and glusterfs replica 2.<br /></blockquote><br />gluster replica 2 is not supported.<br /><br />Nir<br /></pre></blockquote></div></body></html> ------M6FE3B9WI3I917IEZZJ7YA45LB4T6Q--
This is a multi-part message in MIME format. --------------000602080207080006000308 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit On 10/18/2015 07:27 PM, Nicolas LIENARD wrote:
Hey Nil
What about https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volume... ?
Regards Nico
Le 18 octobre 2015 15:12:23 GMT+02:00, Nir Soffer <nsoffer@redhat.com> a écrit :
On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <gluster@distran.org> wrote:
Hi Currently, i ve 3 nodes, 2 in same DC and a third in another DC. They are all bridged together through a vpn. I know a cluster is at least 3 nodes to satisfy the quorum.
Just adding a 3rd node (without actually using it for 3 way replication) might not help in preventing split-brains. gluster has client-quorum and server-quorum. Have a look at http://comments.gmane.org/gmane.comp.file-systems.gluster.user/22609 for some information. If you are indeed using it as a replica-3, then it is better to have all 3 nodes in the same DC. gluster clients sends every write() to all bricks of the replica (and waits for their responses too), so if one of them is in another DC, it might slow writes due to network latency.
My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2.
replica 2 definitely provides HA but if you have more chances of files ending in split-brain if you have frequent network disconnects , which is why replica 3 with client-quorum set to 'auto' is better for preventing split-brains. arbiter-volumes are a kind of a sweet-spot between replica-2 and replica-3 that can prevent split-brains. The link that Nir shared describes it and how to create one etc. Regards, Ravi
gluster replica 2 is not supported.
Nir
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
--------------000602080207080006000308 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 8bit <html> <head> <meta content="text/html; charset=windows-1252" http-equiv="Content-Type"> </head> <body text="#000000" bgcolor="#FFFFFF"> <br> <br> <div class="moz-cite-prefix">On 10/18/2015 07:27 PM, Nicolas LIENARD wrote:<br> </div> <blockquote cite="mid:999EFF8B-4E1E-4776-823B-54A4BF6DFE25@distran.org" type="cite">Hey Nil <br> <br> What about <a moz-do-not-send="true" href="https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volumes">https://gluster.readthedocs.org/en/release-3.7.0/Features/afr-arbiter-volumes</a>/ ?<br> <br> Regards<br> Nico <br> <br> <br> <div class="gmail_quote">Le 18 octobre 2015 15:12:23 GMT+02:00, Nir Soffer <a class="moz-txt-link-rfc2396E" href="mailto:nsoffer@redhat.com"><nsoffer@redhat.com></a> a écrit : <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <pre class="k9mail">On Sat, Oct 17, 2015 at 12:45 PM, Nicolas LIENARD <a class="moz-txt-link-rfc2396E" href="mailto:gluster@distran.org"><gluster@distran.org></a> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> Hi Currently, i ve 3 nodes, 2 in same DC and a third in another DC. They are all bridged together through a vpn. I know a cluster is at least 3 nodes to satisfy the quorum. </blockquote></pre> </blockquote> </div> </blockquote> <br> <br> Just adding a 3rd node (without actually using it for 3 way replication) might not help in preventing split-brains. gluster has client-quorum and server-quorum. Have a look at <a class="moz-txt-link-freetext" href="http://comments.gmane.org/gmane.comp.file-systems.gluster.user/22609">http://comments.gmane.org/gmane.comp.file-systems.gluster.user/22609</a> for some information.<br> <br> If you are indeed using it as a replica-3, then it is better to have all 3 nodes in the same DC. gluster clients sends every write() to all bricks of the replica (and waits for their responses too), so if one of them is in another DC, it might slow writes due to network latency.<br> <blockquote cite="mid:999EFF8B-4E1E-4776-823B-54A4BF6DFE25@distran.org" type="cite"> <div class="gmail_quote"> <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <pre class="k9mail"><blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> My question is to know if i can have my VM balancing on the 2 fast nodes with HA and glusterfs replica 2. </blockquote></pre> </blockquote> </div> </blockquote> <br> <br> replica 2 definitely provides HA but if you have more chances of files ending in split-brain if you have frequent network disconnects , which is why replica 3 with client-quorum set to 'auto' is better for preventing split-brains.<br> arbiter-volumes are a kind of a sweet-spot between replica-2 and replica-3 that can prevent split-brains. The link that Nir shared describes it and how to create one etc.<br> <br> Regards,<br> Ravi<br> <blockquote cite="mid:999EFF8B-4E1E-4776-823B-54A4BF6DFE25@distran.org" type="cite"> <div class="gmail_quote"> <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <pre class="k9mail"> gluster replica 2 is not supported. Nir </pre> </blockquote> </div> <br> <fieldset class="mimeAttachmentHeader"></fieldset> <br> <pre wrap="">_______________________________________________ Users mailing list <a class="moz-txt-link-abbreviated" href="mailto:Users@ovirt.org">Users@ovirt.org</a> <a class="moz-txt-link-freetext" href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a> </pre> </blockquote> <br> </body> </html> --------------000602080207080006000308--
participants (4)
-
Nicolas LIENARD -
Nir Soffer -
Ravishankar N -
Yaniv Kaul