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On 09/09/2015 10:14 AM, Richard Neuboeck wrote: <br>
<font color="#000000">> On 04.09.15 10:02, Simone Tiraboschi wrote: </font><br>
<font color="#000000">>> Is there a reason why it has to be exactly replica 3? </font><br>
<font color="#000000">>> </font><br>
<font color="#000000">>> </font><br>
<font color="#000000">>> To have a valid quorum having the system being able to decide witch is </font><br>
<font color="#000000">>> the right and safe copy avoiding an issue called split brain. </font><br>
<font color="#000000">>> Under certain circumstances/issues (network issue, hosts down or </font><br>
<font color="#000000">>> whatever could happen) the data on different replica could diverge: if </font><br>
<font color="#000000">>> you have two and just two different hosts that claim each other </font><br>
<font color="#000000">> that its </font><br>
<font color="#000000">>> copy is the right one there is no way to automatically take the right </font><br>
<font color="#000000">>> decision. Having three hosts and setting the quorum according to that </font><br>
<font color="#000000">>> solves/mitigates the issue. </font><br>
<font color="#000000">> </font><br>
<font color="#000000">> Thanks for the explanation. I do understand the problem but since </font><br>
<font color="#000000">> I'm somewhat limited in my hardware options is there a way to </font><br>
<font color="#000000">> override this requirement? Meaning if I change the checks for </font><br>
<font color="#000000">> replica 3 in the installation scripts does something else fail on </font><br>
<font color="#000000">> the way? </font><br>
<font color="#000000">> </font><br>
<font color="#000000">> In my case coherence checks would come from outside the storage and </font><br>
<font color="#000000">> vm host setup and fencing would be applied appropriately. </font><br>
<font color="#000000">> </font><br>
<font color="#000000">> I would very much appreciate it if the particulars of the storage </font><br>
<font color="#000000">> setup could be either selected from a list of possibilities or be </font><br>
<font color="#000000">> ignored and just a warning be issued that this setup is not recommended. </font><br>
<font color="#000000">> </font><br>
<font color="#000000">> Thanks! </font><br>
<font color="#000000">> Richard </font><br>
<font color="#000000">> </font><br>
<font color="#000000">> </font><br>
As a side question, in Glusterfs 3.7 there is an "AFR arbiter volume" <br>
(<a href="http://gluster.readthedocs.org/en/release-3.7.0-1/Features/afr-arbiter-volumes/">http://gluster.readthedocs.org/en/release-3.7.0-1/Features/afr-arbiter-volumes/</a>) <br>
that will only contain the metadata. <br>
<br>
Will ovirt support this in 3.6? <br>
<br>
Kind regards, <br>
<br>
Jorick Astrego <br>
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<b style="color:#604c78"></b><br><br><span style="color:#604c78;"><font color="000000"><span style="mso-fareast-language:en-gb;" lang="NL">Met vriendelijke groet, With kind regards,<br><br>Jorick Astrego<br></span></font></span><b style="color:#604c78"><br>Netbulae Virtualization Experts </b><br><hr style="border:none;border-top:1px solid #ccc;"><table style="width: 522px"><tbody><tr><td style="width: 130px;font-size: 10px">Tel: 053 20 30 270</td> <td style="width: 130px;font-size: 10px">info@netbulae.eu</td> <td style="width: 130px;font-size: 10px">Staalsteden 4-3A</td> <td style="width: 130px;font-size: 10px">KvK 08198180</td></tr><tr> <td style="width: 130px;font-size: 10px">Fax: 053 20 30 271</td> <td style="width: 130px;font-size: 10px">www.netbulae.eu</td> <td style="width: 130px;font-size: 10px">7547 TA Enschede</td> <td style="width: 130px;font-size: 10px">BTW NL821234584B01</td></tr></tbody></table><br><hr style="border:none;border-top:1px solid #ccc;"><BR />
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