[pgpool-general: 9179] Pgpool-II 4.4.4 Split-brain situation

[Pradeep Prajapati]

Hello Team,

I Need help or suggestions on the issue below pgpool-II.

Example:-
Node1 -- Primary (Postgres & pgpool installed)
Node2 -- Standby (Postgres & pgpool installed)
Node3 -- Witness  (Pgpool installed)

Incident:-

1. In the pgpool cluster we have node1 is primary, node2 is secondary, and
node3 is witness.
2. node1 becomes unresponsive then failover is triggered and then node2
becomes the new primary.
3. After 15 minutes node1 became responsive again and node1 is in primary
state and we have node 2 also in primary so a split brain situation
happened.
4. Node 1 itself is decided as leader/coordinator based on the node 1
pgpool record and more number of connected standby nodes (based on old
state of information) , now i am the true leader, it is decided as the true
leader and asks node 2 to step down.
5. In this case for 15 minutes data written to node 2 new primary after
node 1 responsive data gets started to return on node 1 again so here data
gets inconsistent.

Please provide a suggestion in this case.

NOTE:- We are using only for auto-failover not for auto-failback so
auto-failback is disabled.

Thanks & Regards,
Pradeep Prajapati
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