<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif">Hi Jose,</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Thanks for the response. That was quite helpful. So in our case, there will not be frequent volume create/delete. Not at all. Once done during initial setup, it should continue unless we face some space crunch. :) Based on your quote that <i>actual I/O</i> will not be interrupted/affected, it seems running a single node Heketi cluster in Kubernetes should be just fine.</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Thank You! :)</div><div class="gmail_default" style="font-family:verdana,sans-serif">Gaurav</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Sep 28, 2017 at 9:58 PM, Jose A. Rivera <span dir="ltr"><<a href="mailto:jarrpa@redhat.com" target="_blank">jarrpa@redhat.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">In regular usage the heketi service is only used for the creation and<br>
deletion of GlusterFS volumes. That is, only as PV/PVC pairs are<br>
created or deleted. heketi's presence is not needed for when<br>
applications want to mount and read/write to the volumes. If you have<br>
a constant stream of volume create/delete requests then yes you'll<br>
experience a few seconds of service interruption, but the actual I/O<br>
work would not be affected.<br>
<span class="HOEnZb"><font color="#888888"><br>
--Jose<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
On Thu, Sep 28, 2017 at 9:28 AM, Gaurav Chhabra<br>
<<a href="mailto:varuag.chhabra@gmail.com">varuag.chhabra@gmail.com</a>> wrote:<br>
> Hi Talur,<br>
><br>
><br>
> Since there will be many applications which will be using Gluster volumes, i<br>
> would really prefer if i could ensure maximum availability. From what i<br>
> understand, since Heketi is managing Gluster and while creating storage<br>
> class, we specify the Heketi REST URL, so if it goes down, i hope<br>
> application pods will be affected, isn't it? If replicas is not feasible,<br>
> what are the options i can explore?<br>
><br>
><br>
> Regards,<br>
> Gaurav<br>
><br>
><br>
> On Thu, Sep 28, 2017 at 5:39 PM, Raghavendra Talur <<a href="mailto:rtalur@redhat.com">rtalur@redhat.com</a>><br>
> wrote:<br>
>><br>
>> On Wed, Sep 27, 2017 at 11:15 PM, Gaurav Chhabra<br>
>> <<a href="mailto:varuag.chhabra@gmail.com">varuag.chhabra@gmail.com</a>> wrote:<br>
>> > Hello Everyone,<br>
>> ><br>
>> ><br>
>> > I want to install Heketi server and client on Kubernetes. To ensure HA,<br>
>> > i<br>
>> > would like to have replica set to 2 for it. However, i am not sure about<br>
>> > the<br>
>> > Heketi db. Does it contain only static data about volumes, nodes etc<br>
>> > (and<br>
>> > changes only when we perform some explicit operations such as add<br>
>> > volumes<br>
>> > etc) OR will it create issues (concurrent write) if i have two replicas<br>
>> > running?<br>
>> ><br>
>><br>
>> Yes, heketi updates the db only when a operation is performed. But<br>
>> replica set 2 won't work because bolt db opens the db file with read<br>
>> write lock and the second instance will fail to get one. You will end<br>
>> up with 2nd instance in read only mode.<br>
>><br>
>> If I get it right, you are saying you can't afford to have heketi pod<br>
>> down even for the time duration when kubernetes respins the pod when<br>
>> it detects it is down?<br>
>><br>
>> ><br>
>> > Thanks,<br>
>> > Gaurav<br>
>> ><br>
>> > ______________________________<wbr>_________________<br>
>> > heketi-devel mailing list<br>
>> > <a href="mailto:heketi-devel@gluster.org">heketi-devel@gluster.org</a><br>
>> > <a href="http://lists.gluster.org/mailman/listinfo/heketi-devel" rel="noreferrer" target="_blank">http://lists.gluster.org/<wbr>mailman/listinfo/heketi-devel</a><br>
>> ><br>
><br>
><br>
><br>
> ______________________________<wbr>_________________<br>
> heketi-devel mailing list<br>
> <a href="mailto:heketi-devel@gluster.org">heketi-devel@gluster.org</a><br>
> <a href="http://lists.gluster.org/mailman/listinfo/heketi-devel" rel="noreferrer" target="_blank">http://lists.gluster.org/<wbr>mailman/listinfo/heketi-devel</a><br>
><br>
</div></div></blockquote></div><br></div>