Configuring Streaming Replication

Configuring a replication scenario can be complex; for detailed information about configuration options, please see the PostgreSQL core documentation, available at:

https://www.postgresql.org/docs/12/static/warm-standby.html#streaming-replication

You may want to use a .pgpass file to enable md5 authentication for the replication user – this may or may not be the safest authentication method for your environment. For more information about the supported authentication options, please see the PostgreSQL core documentation at:

https://www.postgresql.org/docs/12/static/client-authentication.html

Limited Support for Cascading Replication

While Failover Manager does not provide full support for cascading replication, it does provide limited support for simple failover in a cascading replication scenario. Cascading replication allows a Standby node to stream to another Standby node, reducing the number of connections (and processing overhead) to the master node.

cascading replication

Cascading replication.

For detailed information about configuring cascading replication, please see the PostgreSQL documentation at:

https://www.postgresql.org/docs/12/static/warm-standby.html#cascading-replication

To use Failover Manager in a cascading replication scenario, you should modify the cluster properties file, setting the following property values on Standby Node #2:

promotable=false
auto.reconfigure=false

In the event of a Failover, Standby Node #1 will be promoted to the role of Master node. Should failover occur, Standby Node #2 will continue to act as a read-only replica for the new Master node until you take actions to manually reconfigure the replication scenario to contain 3 nodes.

In the event of a failure of Standby Node #1, you will not have failover protection, but you will receive an email notifying you of the failure of the node.

Please note that performing a switchover and switch back to the original master may not preserve the cascading replication scenario.