Check if postgresql is running
===
/etc/rc.d/init.d/postgresql status
/etc/rc.d/init.d/postgresql-9.3 status

Find all processes running under postgres user
===
ps -f -u postgres
ps auxw | grep post

Show the TCP/IP addresses and ports PostgreSQL is listening on
===
lsof -n -u posgres | grep LISTEN
netstat -ltnp | grep postgres

A failure message suggesting that another postmaster is already running should be checked carefully, for example by using the command
===
ps ax | grep postmaster
ps -ef | grep postmaster

Grand sudo access
===
visudo

Secure access by disabling root and giving your Linux user account an ssh key
===
On remote terminal:
cd (homedir)
mkdir .ssh
touch .ssh/authorized_keys
on remote machine:
cat .ssh/id_rsa.pub
copy
On remote terminal:
paste key into .ssh/authorized_keys
Logon as root:
sudo su -
mv .ssh/authorized_keys .ssh/authorized_keys_OLD

Edit pg_hba.conf
===
vi /etc/postgresql/9.3/pg_hba.conf