Find the host name and port using PSQL commands

SELECT *
FROM pg_settings
WHERE name = 'port';

This command will give you postgres port number

 \conninfo

If postgres is running on Linux server, you can also use the following command

sudo netstat -plunt |grep postgres

OR (if it comes as postmaster)

sudo netstat -plunt |grep postmaster

and you will see something similar as this

tcp        0      0 127.0.0.1:5432          0.0.0.0:*               LISTEN      140/postgres
tcp6       0      0 ::1:5432                :::*                    LISTEN      140/postgres

in this case, port number is 5432 which is also default port number

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