1.Download and install it using the appropriate package management

~ $ rpm -Uvh https://yum.postgresql.org/9.4/redhat/rhel-7-x86_64/pgdg-centos94-9.4-3.noarch.rpm
Retrieving https://yum.postgresql.org/9.4/redhat/rhel-7-x86_64/pgdg-centos94-9.4-3.noarch.rpm
warning: /var/tmp/rpm-tmp.IZow7N: Header V4 DSA/SHA1 Signature, key ID 442df0f8: NOKEY
Preparing... ################################# [100%]
Updating / installing...
1:pgdg-redhat-repo-42.0-4 ################################# [100%]

2. Applying any necessary updates.

[root@tcox6 ~]# yum update

3. Install the PostgreSQL 9.4 server and associated contribed modules and utilities. Once installed, run the database initialization routine before starting the database.

[root@tcox6 ~]# yum install postgresql94-server postgresql94-contrib

4. Enable the PostgreSQL 9.4 server to run on system start and then start the database server.

[root@tcox6 ~]# systemctl enable postgresql-9.4

ln -s '/usr/lib/systemd/system/postgresql-9.4.service' '/etc/systemd/system/multi-user.target.wants/postgresql-9.4.service'

[root@tcox6 ~]# systemctl start postgresql-9.4

5. Check to see if SELinux is being run in enforced mode on your system. If so, run the command to allow external HTTP DB connections to the server through SELinux configuration.

# cat /etc/selinux/config

# This file controls the state of SELinux on the system.

# SELINUX= can take one of these three values:

#     enforcing - SELinux security policy is enforced.

#     permissive - SELinux prints warnings instead of enforcing.

#     disabled - No SELinux policy is loaded.

SELINUX=enforcing

# SELINUXTYPE= can take one of these two values:

#     targeted - Targeted processes are protected,

#     minimum - Modification of targeted policy. Only selected processes are protected.

#     mls - Multi Level Security protection.

SELINUXTYPE=targeted

# setsebool -P httpd_can_network_connect_db 1

6. Login to the ‘postgres’ user and run the ‘psql’ command. Once at the database prompt, set a password for the ‘psql’ user.

[root@tcox6 ~]# su - postgres

Last login: Wed Sep  2 13:35:21 UTC 2015 on pts/0

-bash-4.2$ psql

psql (9.4.4)

Type "help" for help.

 

postgres=# \password postgres

Enter new password:

Enter it again:

postgres=# quit

postgres-# \q

-bash-4.2$ exit

logout