Openstack-Keystone failing to start

If openstack-Keystone is not starting:

for eg:

 [root@* keystone]# service openstack-keystone restart

Stopping keystone:                                         [FAILED]
Starting keystone:                                         [  OK  ]
[root@* keystone]# service openstack-keystone restart
Stopping keystone:                                         [FAILED]
Starting keystone:                                         [  OK  ]

Try running keystone manually instead of as a service:

$ sudo -u keystone bash
$ HOME=/var/lib/keystone keystone-all --debug