could not connect to server: Connection refused Is the server running on host and accepting TCP/IP connections on port 5432?
cd /etc/postgresql/9.x/main/ ------- open file named postgresql.conf sudo nano postgresql.conf ------- add this line to that file listen_addresses = '*' ------- then open file named pg_hba.conf sudo nano pg_hba.conf ------- and add this line to that file host all all 0.0.0.0/0 md5 ------- restart your server sudo /etc/init.d/postgresql restart