title: Failure trying to start devstack
body: <p>I have a devstack environment (Installed on Ubuntu 14.04.1 LTS) with which I have been working for a while now.</p>
  
  <p>Started getting this error when I run the <strong>stack.sh</strong> script</p>
  
  <p><strong>ERROR: openstack Authentication failure: An unexpected error prevented the server from fulfilling your request: No module named backends.sql (Disable debug mode to suppress these details.) (HTTP 500)</strong></p>
  
  <p>Things I have tried.</p>
  
  <ul>
  <li>Restarted the devstack VM </li>
  <li>Reinstalled mysql-server</li>
  <li>Cloned a new copy of devstack to run a fresh copy of the code</li>
  </ul>
  
  <p>Note that I can login to MySQL using the credentials I have in my local.conf and the same configurations were working for the past couple of months </p>
  
  <p>If any other information is needed, please let me know.</p>
  
  <p>More detailed log:</p>
  
  <pre><code>2014-12-18 22:28:13.530 | ++ ENABLED_SERVICES=g-api,g-reg,key,n-api,n-crt,n-obj,n-cpu,n-net,n-cond,n-sch,n-novnc,n-xvnc,n-cauth,c-sch,c-api,c-vol,h-eng,h-api,h-api-cfn,h-api-cw,horizon,rabbit,tempest,mysql,ceilometer-acompute,ceilometer-acentral,ceilometer-anotification,ceilometer-collector,ceilometer-alarm-evaluator,ceilometer-alarm-notifier,ceilometer-api
  2014-12-18 22:28:13.530 | ++ is_service_enabled gantt
  2014-12-18 22:28:13.533 | ++ return 1
  2014-12-18 22:28:13.533 | + for i in '$TOP_DIR/extras.d/*.sh'
  2014-12-18 22:28:13.534 | + [[ -r /home/hellraiser/newicehouse/extras.d/70-marconi.sh ]]
  2014-12-18 22:28:13.534 | + source /home/hellraiser/newicehouse/extras.d/70-marconi.sh stack post-config
  2014-12-18 22:28:13.534 | ++ is_service_enabled marconi-server
  2014-12-18 22:28:13.536 | ++ return 1
  2014-12-18 22:28:13.536 | + for i in '$TOP_DIR/extras.d/*.sh'
  2014-12-18 22:28:13.536 | + [[ -r /home/hellraiser/newicehouse/extras.d/70-sahara.sh ]]
  2014-12-18 22:28:13.536 | + source /home/hellraiser/newicehouse/extras.d/70-sahara.sh stack post-config
  2014-12-18 22:28:13.536 | ++ is_service_enabled sahara
  2014-12-18 22:28:13.539 | ++ return 1
  2014-12-18 22:28:13.540 | + for i in '$TOP_DIR/extras.d/*.sh'
  2014-12-18 22:28:13.540 | + [[ -r /home/hellraiser/newicehouse/extras.d/70-trove.sh ]]
  2014-12-18 22:28:13.540 | + source /home/hellraiser/newicehouse/extras.d/70-trove.sh stack post-config
  2014-12-18 22:28:13.540 | ++ is_service_enabled trove
  2014-12-18 22:28:13.543 | ++ return 1
  2014-12-18 22:28:13.543 | + for i in '$TOP_DIR/extras.d/*.sh'
  2014-12-18 22:28:13.543 | + [[ -r /home/hellraiser/newicehouse/extras.d/80-opendaylight.sh ]]
  2014-12-18 22:28:13.543 | + source /home/hellraiser/newicehouse/extras.d/80-opendaylight.sh stack post-config
  2014-12-18 22:28:13.543 | ++ is_service_enabled odl-server odl-compute
  2014-12-18 22:28:13.546 | ++ return 1
  2014-12-18 22:28:13.546 | ++ is_service_enabled odl-server
  2014-12-18 22:28:13.549 | ++ return 1
  2014-12-18 22:28:13.549 | ++ is_service_enabled odl-compute
  2014-12-18 22:28:13.552 | ++ return 1
  2014-12-18 22:28:13.552 | + for i in '$TOP_DIR/extras.d/*.sh'
  2014-12-18 22:28:13.553 | + [[ -r /home/hellraiser/newicehouse/extras.d/80-tempest.sh ]]
  2014-12-18 22:28:13.553 | + source /home/hellraiser/newicehouse/extras.d/80-tempest.sh stack post-config
  2014-12-18 22:28:13.553 | ++ is_service_enabled tempest
  2014-12-18 22:28:13.555 | ++ return 0
  2014-12-18 22:28:13.555 | ++ [[ stack == \s\o\u\r\c\e ]]
  2014-12-18 22:28:13.555 | ++ [[ stack == \s\t\a\c\k ]]
  2014-12-18 22:28:13.555 | ++ [[ post-config == \i\n\s\t\a\l\l ]]
  2014-12-18 22:28:13.555 | ++ [[ stack == \s\t\a\c\k ]]
  2014-12-18 22:28:13.555 | ++ [[ post-config == \p\o\s\t\-\c\o\n\f\i\g ]]
  2014-12-18 22:28:13.555 | ++ create_tempest_accounts
  2014-12-18 22:28:13.555 | ++ is_service_enabled tempest
  2014-12-18 22:28:13.558 | ++ return 0
  2014-12-18 22:28:13.558 | ++ openstack project create alt_demo
  2014-12-18 22:28:14.181 | ERROR: openstack Authentication failure: An unexpected error prevented the server from fulfilling your request: No module named backends.sql (Disable debug mode to suppress these details.) (HTTP 500)
  2014-12-18 22:28:14.212 | + exit_trap
  2014-12-18 22:28:14.213 | + local r=1
  2014-12-18 22:28:14.213 | ++ jobs -p
  2014-12-18 22:28:14.214 | + jobs=
  </code></pre>