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From: a venkatesh <venkatesh.sasi@gmail.com>
Date: Mon, 18 Nov 2019 10:41:12 -0800
Message-ID: 
 <CANLYxgwq-0fOOfdDPPAB9gML45=dqmzFUh=oq-AFTKZcAzRW_w@mail.gmail.com>
Subject: pgpool High Availability Issue
To: pgadmin-hackers@lists.postgresql.org, pgsql-admin@postgresql.org
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Hi,

I'm working on configuring high availability for pgpool using watchdog.
Initially, I tried with two pgpool nodes (along with a pgmaster and
pgslave). In this scenario, assuming pgpool node 1 was started first and
became the leader. After sometime , the node got disconnected with  pgpool
node 2 and pgpool node 2 as well declared itself as leader.


To handle this kind of scenario, I tried provisioning an additional pgpool
node and made a cluster with total 5 nodes (3 pgpool nodes, 1 pgmaster and
1 pgslave), assuming it will create a quorum to handle such situations.
Unfortunately, the situation still remains the same. (In case of any
disconnection between node that became leader and the first stand by node,
both the nodes try to manage the pgmaster and slave simultaneously).

Please help me understand if this is expected behavior or some additional
configurations are required to be made, so that two pgpool nodes don't
become leader simultaneously.  If it's an expected behavior, how can we
handle this ?

(A point to note is that I'm not using elastic IP address here, instead I
have created a network load balancer in AWS, created a target group with
all the three pgpool nodes as targets).

Regards,

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<div dir=3D"ltr">Hi,=C2=A0<div><br></div><div>I&#39;m working on configurin=
g high availability for pgpool using watchdog. Initially, I tried with two =
pgpool nodes (along with a pgmaster and pgslave). In this scenario, assumin=
g pgpool node 1 was started first and became the leader. After sometime , t=
he node got disconnected with=C2=A0 pgpool node 2 and pgpool node 2 as well=
 declared itself as leader.=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=
 =C2=A0 =C2=A0 =C2=A0=C2=A0</div><div><br></div><div>To handle this kind of=
 scenario, I tried provisioning an additional pgpool node and made a cluste=
r with total 5 nodes (3 pgpool nodes, 1 pgmaster and 1 pgslave), assuming i=
t will create a quorum to handle such situations. Unfortunately, the situat=
ion still remains the same. (In case of any disconnection between node that=
 became leader and the first stand by node, both the nodes try to manage th=
e pgmaster and slave simultaneously).<br></div><div><br></div><div>Please h=
elp me understand if this is expected behavior or some additional configura=
tions are required to be made, so that two pgpool nodes don&#39;t become le=
ader simultaneously.=C2=A0 If it&#39;s an expected behavior, how can we han=
dle this ?=C2=A0</div><div><br></div><div>(A point to note is that I&#39;m =
not using elastic IP address here, instead I have created a network load ba=
lancer in AWS, created a target group with all the three pgpool nodes as ta=
rgets).=C2=A0</div><div><br></div><div>Regards,=C2=A0</div></div>

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