we have an odd issue where a java app using JDBC which has been
working fine has suddenly started disconnecting after we setup
replication from the database it was connecting to ( which is now the
primary in a replicating pair ) with errors such as the following...
CLIENT SIDE: DBNAME/logs/20210815-200601.20966.log:SessionManagerImpl
WARN 20210816-00:01:00.252 - A session lost connection with the
database. Disabling all sessions
SERVER SIDE: 2021-08-16 01:48:27 BST FATAL: unsupported frontend
protocol 1234.5680: server supports 1.0 to 3.0
( these are different times but you get the idea )
I appreciate this seems like a JDBC driver issue but everything has
been fine and we observe the errors only once we setup replication.
could there be some issue with streaming / WAL replication that could
be causing this ? we are running 9.6 by the way thanks.