1.
rpm -ivh pgdg-centos96-9.6-1.noarch.rpm
2.
rpm -ivh pgdg-centos96-9.6-1.noarch.rpm
3.
yum -y install postgresql96-server postgresql96-devel postgresql96-contrib

4.
systemctl start postgresql-9.6
(err)
Job for postgresql-9.6.service failed because the control process exited with error code. See "systemctl status postgresql-9.6.service" and "journalctl -xe" for details.
5.
systemctl status postgresql-9.6
(err)
● postgresql-9.6.service - PostgreSQL 9.6 database server
Loaded: loaded (/usr/lib/systemd/system/postgresql-9.6.service; disabled; vendor preset: disabled)
Active: failed (Result: exit-code) since 金 2016-06-24 10:15:44 JST; 37s ago
Process: 4912 ExecStartPre=/usr/pgsql-9.6/bin/postgresql96-check-db-dir ${PGDATA} (code=exited, status=1/FAILURE)
6月 24 10:15:44 localhost.localdomain systemd[1]: Starting PostgreSQL 9.6 database server...
6月 24 10:15:44 localhost.localdomain systemd[1]: postgresql-9.6.service: control process exited, code=exited status=1
6月 24 10:15:44 localhost.localdomain systemd[1]: Failed to start PostgreSQL 9.6 database server.
6月 24 10:15:44 localhost.localdomain systemd[1]: Unit postgresql-9.6.service entered failed state.
6月 24 10:15:44 localhost.localdomain systemd[1]: postgresql-9.6.service failed.
6.
/usr/pgsql-9.6/bin/postgresql96-setup initdb


7.
systemctl start postgresql-9.6
systemctl start postgresql-9.6
systemctl enable postgresql-9.6