FATAL ERROR lock file “postmaster.pid” already exists

Question

I have recently installed PostGIS on my Mac (El Capitan 10.11.4, Postgres is version 9.5.1) using Homebrew, and I am following these instructions - http://morphocode.com/how-to-

Answer 1

It often happens to me in OSx, when my system shutdown unexpectedly.

You can just remove the file postmaster.pid.

cd Library/Application Support/Postgres/var-{postgres-version}

and remove the postmaster.pid file

restart the Postgres by using this command

pg_ctl -D /usr/local/var/postgres restart