Steps to reproduce:

1. Installed zabbix-agent2 5.0.28 from zabbix repository
2. zabbix_agent2.conf has no active parameter related to PostgreSQL
3. On zabbix-server, the host is associated to the DB PotgreSQL Agent 2 template
4. The host has also the following macros set:
   1. $PG.HOST = localhost
   2. $PG.URI = postgresql://localhost:5433
   3. $PG.USER = zbx_monitor
   4. $PG.PORT = 5433

Yes, my PostgreSQL is running on the non-default port 5433.

Result:

The discovery rule Database discovery fails with the following error:

Connection failed: failed to connect to `host=localhost user=postgres database=postgres`: dial error (dial tcp 127.0.0.1:5432: connect: connection refused).

The same message shows up on the zabbix-agent log.

Additional Info:

On the zabbix-server console, I can run:

zabbix_get -s XXX.XXX.XXX.XXX -k 'pgsql.db.discovery[postgresql://localhost:5433,zbx_monitor,,postgres]'

This command returns the correct discovery value. The zabbix_get command bellow:

zabbix_get -s 10.1.1.10 -k 'pgsql.db.discovery[]'

Gives me the same error above.

I have other hosts running PostgreSQL and zabbix-agent2 version 5.0.1. On those hosts, the monitoring is working fine.