When using the OpenStack client to execute Glance-related commands, you can come across a connection error similar to the following one:

This typically indicates a configuration problem wherein Keystone is not accessible at the provided URI. When using the Glance client, this value is typically pulled from the OS_AUTH_URL value in the openrc file. Refer to Chapter 2, Troubleshooting OpenStack Identity, for information about the openrc file. You can find yourself in this situation when the value of your os_auth_url is incorrect. Alternately, this could also be the result of Keystone not running on the expected URI and port. To correct this issue, you will need to update your openrc file with the correct os_auth_url or pass the correct value in as an attribute to your OpenStack CLI commands.

Internal server errors in OpenStack can be tricky because there are several factors that may contribute to these problems. In the context of Glance, if you see an error similar to this, be sure to check the database, making sure that it is running and configured correctly:

When you are searching through your logs, if you come across an error like the following one, this is a clue that there is a problem with the configuration between Glance and Keystone:

If you come across an error like the preceding error, take a look at the /var/log/glance/api.log file. Near this error, look out for a log line similar to the following one:

This error points to the need to confirm your auth_url setting in the glance-api.conf file. The value for this setting should be the URL for your Keystone installation that is accessed on port 35357.