<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Sep 3, 2019 at 7:25 PM Tatsuo Ishii <<a href="mailto:ishii@sraoss.co.jp">ishii@sraoss.co.jp</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">> Hi Ishii-San,<br>
> <br>
> On Tue, Sep 3, 2019 at 5:43 AM Tatsuo Ishii <<a href="mailto:ishii@sraoss.co.jp" target="_blank">ishii@sraoss.co.jp</a>> wrote:<br>
> <br>
>> Hi Usama,<br>
>><br>
>> Can you comment on this:<br>
>> <a href="https://www.pgpool.net/mantisbt/view.php?id=541" rel="noreferrer" target="_blank">https://www.pgpool.net/mantisbt/view.php?id=541</a><br>
>><br>
>> It seems VIP is not set when there's no quorum. Since there's nothing<br>
>> in the docs regarding VIP vs. quorum and I am wondering if this is<br>
>> a feature or a bug.<br>
>><br>
> <br>
> This is a feature and as per the design. The reason for doing this is to<br>
> avoid split-brain syndrome.<br>
> In the absence of a quorum, the watchdog cluster does select a master node<br>
> but waits for the quorum to perform the escalation(bringing up of VIP).<br>
> <br>
> Initially, in the absence of the quorum, the cluster used to abstain from<br>
> selecting the master node but it was causing some synchronization issues so<br>
> the behaviour was modified and now the cluster goes on the elect the master<br>
> node even in the absence of the quorum but does not bring up the<br>
> VIP until it finds the quorum.<br>
> <br>
> Below mentioned commit changed the said behaviour back in 2015<br>
> <br>
> <a href="https://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=6238ba9d2aaa82db415b11aca90d54981a854e09" rel="noreferrer" target="_blank">https://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=6238ba9d2aaa82db415b11aca90d54981a854e09</a><br>
<br>
Thanks for the explanation. One more question.<br>
<br>
Suppose 3 node watchdog configuration. Initially all 3 nodes are up<br>
and VIP is up. Now 2 of 3 nodes go down, and quorum is lost, so the<br>
VIP will be brought down?<br></blockquote><div><br></div><div>Yes, as soon as a quorum is lost the master node will perform the de_escalation and remove the VIP.</div><div><br></div><div>Thanks</div><div>Best regards</div><div>Muhammad Usama</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
Best regards,<br>
--<br>
Tatsuo Ishii<br>
SRA OSS, Inc. Japan<br>
English: <a href="http://www.sraoss.co.jp/index_en.php" rel="noreferrer" target="_blank">http://www.sraoss.co.jp/index_en.php</a><br>
Japanese:<a href="http://www.sraoss.co.jp" rel="noreferrer" target="_blank">http://www.sraoss.co.jp</a><br>
</blockquote></div></div>