You can achieve this HA with forward and backward reverse synchronous streaming replication with 3 nodes automatic failover with pgpool in PostgreSQL.
There is always downtime but it should not be more than a minute its depends on your hardware and network bandwidth speed availability.
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On Tue, Feb 6, 2018 at 4:31 PM, Dhandapani Shanmugam <postgresql95@xxxxxxxxx> wrote:
Hi Gurus,Do we have active-active setup in postgreSQL, like we have in oracle RAC?. Sorry if this question has been addressed already. What will be best open source HA for postgresql with zero RTO and RPO.-D