Some questions about Keystone: stop:unknow instance or unable to establish connection to http://controller:35357/v2.0/

I've been taking OpenStack recently, and I've stepped on a lot of holes, mostly in official documents, or problems; Here's a suggestion: try not to take Liberty (launched in October 2015), because the launch of the time is not long, many problems have not been solved, but also imperfect, Therefore, it is recommended to carry J or K version;

The system I'm using is: Ubuntu server 14.04, trying to carry the juno:http://docs.openstack.org/juno/install-guide/install/apt/content/ch_preface.html

In the keystone of the identify, I met a lot of pits:

When executing the following statement: (# begins with a statement executed with root permission)

# Keystone Tenant-create--name admin--description "admin tenant"

An error has occurred: Unable to establish connection to http://controller:35357/v2.0/tenant, the problem cannot be connected. Some possible errors have been ruled out: such as the problem of can ' t connect to MySQL server on ' controller ';

Re-execute the process again according to the official document, or the same problem, watch the video operation on the Youbute, when viewing the user-list:

# Keystone User-list

After the statement is executed, it appears Unable to establish connection to Http://controller:35357/v2.0/userQuestion, or the same problem.

After searching, it may be because Keystone is not restarted:

# Service Keystone Restart

The execution of the statement appears: Stop:unknow instance:keystone start/running, process 3498

It's another one. Search: The same problem is encountered: Do not use restart, split into stop and start:

# service Keystone Stop
# service Keystone Start

After execution, there is no effect, there is the same problem.

There are other people saying: Uninstall Keystone and reinstall the execution:

# Apt-get Remove Keystone
# Apt-get Install Keystone

Later, after start, I looked at the status through the following statement:

# Service Keystone Status

Discover that the service that was already started is closed again, that is, the stop state, which is why we have been wrong: the startup Keystone is soon shut down, causing the connection to fail with the Unknow instance or unable to establish connection problem.

Finally, luckily, a buddy solved my problem:

Modify/etc/keystone/keystone.conf, the driver in the [token] section, originally:

Driver = Keystone.token.persistence.backends.sql.Token

Delete the persistence inside.That is

Driver = Keystone.token.backends.sql.Token

After start, the status is checked and the Keystone has been started and has not been shut down.

Of course, the subsequent statement execution will have no other problem, problem solving (*^__^*)

Good Night ~