If you've ever dealt a bit more seriously with PostgreSQL, and gone through different online articles and examples, chances are that you've ran to
pg_ctl command. Being Ubuntu user, I've often wondered what is the difference between starting PostgreSQL by using Ubuntu-native
service command and
pg_ctl. After some research I've found out what is the catch, and here I'll share this with you.
In some cases you'll want to be able to SSH another server, without being prompted for password. For example, when dealing with PostgreSQL replication you'll need to execute a command on another server as
$ ssh -T postgres@OTHERHOST /etc/postgresql/9.5/main/replscripts/disable_postgresql.sh
In such cases you'll want to avoid password prompt for many reasons, i.e.: