This is a multi-part message in MIME format. --------------050708010909020807020403 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit On 05/12/2016 05:35 AM, Bill Bill wrote:
Hello,
Lets say I have a 5 node converged cluster of oVirt & glusterFS with a replica count of 3.
Host1 - replica
Host2 - replica
Host3 - replica
Host4
Host5
If I spin a VM up on Host1 does the first replica get created local to that server?
In the event I move the VM to another host, does the replica of the disk follow the VM so essentially its writing to a local copy first or does it always write across the network.
Any writes are written to all 3 hosts that form the replica 3 gluster volume. Replica 3 - indicates that there is a 3-way copy of data, and the same data resides on Host1, Host2 and Host3. Reads however are from local host. So for a VM running on Host1, it will access the data (i.e. read) from the brick on Host1.
For example, with VMware, the disk will follow the VM to the hypervisor you move it to so that the writes are essentially local.
I have not been able to find anything on the internet or in the documentation that specifies how this process works. Ideally, you wouldnt want a VM residing on Host1 that accesses its disk on Host3. Multiple that by hundreds of VMs and it would create a ton of unnecessary network congestion.
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
--------------050708010909020807020403 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 05/12/2016 05:35 AM, Bill Bill wrote:<br> </div> <blockquote cite="mid:SN1PR08MB1389E9AA24246B61EE308341A6730@SN1PR08MB1389.namprd08.prod.outlook.com" type="cite"> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style><!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0in; margin-bottom:.0001pt; font-size:11.0pt; font-family:"Calibri",sans-serif;} a:link, span.MsoHyperlink {mso-style-priority:99; color:blue; text-decoration:underline;} a:visited, span.MsoHyperlinkFollowed {mso-style-priority:99; color:#954F72; text-decoration:underline;} .MsoChpDefault {mso-style-type:export-only;} @page WordSection1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in;} div.WordSection1 {page:WordSection1;} --></style> <div class="WordSection1"> <p class="MsoNormal">Hello,</p> <p class="MsoNormal"> </p> <p class="MsoNormal">Lets say I have a 5 node converged cluster of oVirt & glusterFS with a replica count of 3.</p> <p class="MsoNormal"> </p> <p class="MsoNormal">Host1 - replica</p> <p class="MsoNormal">Host2 - replica</p> <p class="MsoNormal">Host3 - replica</p> <p class="MsoNormal">Host4</p> <p class="MsoNormal">Host5</p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">If I spin a VM up on Host1 does the first replica get created local to that server?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">In the event I move the VM to another host, does the replica of the disk follow the VM so essentially its writing to a local copy first or does it always write across the network.</span></p> </div> </blockquote> <br> Any writes are written to all 3 hosts that form the replica 3 gluster volume. Replica 3 - indicates that there is a 3-way copy of data, and the same data resides on Host1, Host2 and Host3. <br> <br> Reads however are from local host. So for a VM running on Host1, it will access the data (i.e. read) from the brick on Host1.<br> <br> <blockquote cite="mid:SN1PR08MB1389E9AA24246B61EE308341A6730@SN1PR08MB1389.namprd08.prod.outlook.com" type="cite"> <div class="WordSection1"> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">For example, with VMware, the disk will follow the VM to the hypervisor you move it to so that the writes are essentially local. </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif">I have not been able to find anything on the internet or in the documentation that specifies how this process works. Ideally, you wouldnt want a VM residing on Host1 that accesses its disk on Host3. Multiple that by hundreds of VMs and it would create a ton of unnecessary network congestion.</span></p> <p class="MsoNormal"><o:p> </o:p></p> </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> --------------050708010909020807020403--