2015-07-08 19:24:10 INFO 3775 (bootstrap) bootstrap upgrader: rollbacked
2015-07-08 19:24:10 DEBUG 3775 (upgrade) HostSystemUpgrader: rollbacking...
2015-07-08 19:24:10 DEBUG 3775 (utils) Remove file "/etc/yum.repos.d/6.0_nailgun.repo"
2015-07-08 19:24:10 ERROR 3775 (upgrade) *** UPGRADE FAILED
2015-07-08 19:24:10 ERROR 3775 (cli) 401 Client Error: Unauthorized
Traceback (most recent call last):
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/cli.py", line 177, in main
    run_upgrade(parse_args(sys.argv[1:]))
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/cli.py", line 169, in run_upgrade
    upgrade_manager.run()
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/upgrade.py", line 51, in run
    upgrader.upgrade()
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/engines/openstack.py", line 61, in upgrade
    self.install_releases()
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/engines/openstack.py", line 144, in install_releases
    existing_releases = self.nailgun.get_releases()
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/fuel_upgrade/clients/nailgun_client.py", line 49, in get_releases
    r.raise_for_status()
  File "/var/tmp/upgrade/.fuel-upgrade-venv/lib/python2.6/site-packages/requests/models.py", line 773, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
HTTPError: 401 Client Error: Unauthorized
==================================================
Upgrade failed