I'm trying setup Openstack multi node environment in my CentOS VM. I've successfully installed the openstack Queens v. in both controllernode and compute node. When i try to create a service in controllernode, its throwing the following error: Internal Server Error (HTTP 500)

The command is: openstack service create --name keystone --description "OpenStack Identity" identity

The keystone.log file is as follows:

2018-07-24 11:10:19.210 5770 WARNING oslo_log.versionutils [-] Deprecated: UUID Token Provider "[token] provider=uuid" is deprecated as of Pike in favor of Fernet token Provider "[token] provider=fernet" and may be removed in R. 
2018-07-24 11:10:19.212 5770 WARNING oslo_config.cfg [-] Option "driver" from group "token" is deprecated for removal.  Its value may be silently ignored in the future. 
2018-07-24 11:10:19.213 5770 WARNING stevedore.named [-] Could not load memcache

The Keystone Bootstrap command is as follows:

keystone-manage bootstrap --bootstrap-password openstack --bootstrap-admin-url http://controllernode1:5000/v3/ --bootstrap-internal-url http://controllernode1:5000/v3/ --bootstrap-public-url http://controllernode1:5000/v3/ --bootstrap-region-id RegionOne

The environment variables are as follows:

OS_USER_DOMAIN_NAME=Default
OS_PROJECT_NAME=admin
OS_IDENTITY_API_VERSION=3
OS_PASSWORD=openstack
OS_AUTH_URL=http://controllernode1:5000/v3
OS_USERNAME=admin
OS_PROJECT_DOMAIN_NAME=Default

Error in the Keystone-error.log:

2018-07-26 14:42:21.279222 ImportError: (u'Unable to find %(name)r driver in %(namespace)r.', {'namespace': 'keystone.token.persistence', 'name': 'memcache'})
2018-07-26 14:42:25.097350 mod_wsgi (pid=7468): Target WSGI script '/usr/bin/keystone-wsgi-public' cannot be loaded as Python module.
2018-07-26 14:42:25.097435 mod_wsgi (pid=7468): Exception occurred processing WSGI script '/usr/bin/keystone-wsgi-public'.
2018-07-26 14:42:25.097503 Traceback (most recent call last):
2018-07-26 14:42:25.097549   File "/usr/bin/keystone-wsgi-public", line 54, in <module>
2018-07-26 14:42:25.097773     application = initialize_public_application()
2018-07-26 14:42:25.097812   File "/usr/lib/python2.7/site-packages/keystone/server/wsgi.py", line 134, in initialize_public_application
2018-07-26 14:42:25.098076     config_files=_get_config_files())
2018-07-26 14:42:25.098123   File "/usr/lib/python2.7/site-packages/keystone/server/wsgi.py", line 66, in initialize_application
2018-07-26 14:42:25.098185     startup_application_fn=loadapp)
2018-07-26 14:42:25.098216   File "/usr/lib/python2.7/site-packages/keystone/server/common.py", line 46, in setup_backends
2018-07-26 14:42:25.098381     drivers = backends.load_backends()
2018-07-26 14:42:25.098418   File "/usr/lib/python2.7/site-packages/keystone/server/backends.py", line 55, in load_backends
2018-07-26 14:42:25.098589     drivers = {d._provides_api: d() for d in managers}
2018-07-26 14:42:25.098653   File "/usr/lib/python2.7/site-packages/keystone/server/backends.py", line 55, in <dictcomp>
2018-07-26 14:42:25.098713     drivers = {d._provides_api: d() for d in managers}
2018-07-26 14:42:25.098743   File "/usr/lib/python2.7/site-packages/keystone/token/persistence/core.py", line 48, in __init__
2018-07-26 14:42:25.099084     super(PersistenceManager, self).__init__(CONF.token.driver)
2018-07-26 14:42:25.099129   File "/usr/lib/python2.7/site-packages/keystone/common/manager.py", line 181, in __init__
2018-07-26 14:42:25.099357     self.driver = load_driver(self.driver_namespace, driver_name)
2018-07-26 14:42:25.099392   File "/usr/lib/python2.7/site-packages ...