I was discussing with one of my friend who is a Developer, as he was working with PostgreSQL 9.5 in Ubuntu 16.04LTS from past few months. But suddenly he couldn’t able to start PostgreSQL service. He tried to reinstall PostgreSQL many times, but no luck. So he gave his laptop to me and asked to fix this issue.(Because of Im a DBA 🙂 ). The very first thing I started to look at the Postgresql logs. Unfortunately, nothing was there. So I checked the syslog file and found something wrong. It was showing the error in Postgrsql Insecure directory in env path.