======Install Postgresql======
This page shows how to install Postgresql on on CentOS 6 64bit.
=====Prerequisites=====
You must have a CentOS machine already set up in accordance with the the [[linux:install_centos6|Install CentOS 6]] guide.
=====Install Postgresql=====
Run the following as root<code>yum install postgresql postgresql-server
chkconfig postgresql on
service postgresql initidb
service postgresql start</code>
Set the password for the user 'postgres'
<code>echo "postgres:pa55w0rd" | chpasswd</code>
=====Configure Firewall=====
Postgresql listens on port 5432.
<code>iptables -I INPUT -m state --state NEW -m tcp -p tcp --dport 5432 -j ACCEPT
service iptables save
service iptables restart</code>
=====Connect to Postgreql=====
Connect using psql command line tool<code>su - postgres
psql -d template1 -U postgres</code>
=====Create Database=====
Connect using psql and run the following. DATABSE_NAME as appropriate.<code>create database DATABASE_NAME;
\q</code>
=====Create Postgresql User=====
Connect using psql and run the following. Replace USERNAME, PASSWORD and DATABSE_NAME as appropriate<code>create user USERNAME with password 'PASSWORD';
grant all privileges on database DATABASE_NAME to USERNAME;
\q</code>
To allow other machines to connect to postgresql, you will need to do the following:

vi /var/lib/pgsql/data/pg_hba.con   (OR /etc/postgresql/8.2/main/pg_hba.conf for latest 8.2 version)
<code>host all all 172.16.0.0/16 trust</code>
(I had to rename all 'ident' to 'trust' to get it to work)

vi /var/lib/pgsql/data/postgresql.conf 
change 
<code>listen_addresses='localhost'</code>
to
<code>listen_addresses='*'</code>
or
<code>listen_addresses='202.54.1.2 202.54.1.3'</code>

<code>service postgresql reload</code>