Horizon sessions storage is not compatible with HA

[Igor Yozhikov]

SESSION_ENGINE variable is not defined in the /etc/openstack-dashboard/local_settings.py and default value used from /usr/share/openstack-dashboard/openstack_dashboard/settings.py in the environment, deployed by FUEL.
SESSION_ENGINE = 'django.contrib.sessions.backends.signed_cookies'
This affects HA mode and murano-dashboard functionality.

 There is solution for this case - use django.contrib.sessions.backends.cache as SESSION_ENGINE.
SESSION_ENGINE = 'django.contrib.sessions.backends.cache' (https://review.openstack.org/#/c/84088/1)

[Sergey Vasilenko (xenolog)]

https://review.openstack.org/#/c/85728/
https://review.openstack.org/#/c/84088/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/4.1
Review: https://review.openstack.org/85943

[Bogdan Dobrelya (bogdando)]

Please abandon 85728 backport due to wrong change-id, a new one is 85943

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/84088
Committed: https://git.openstack.org/cgit/stackforge/fuel-library/commit/?id=00c7a74490e584aa3287ea13bedd00ae8eeb228a
Submitter: Jenkins
Branch: master

commit 00c7a74490e584aa3287ea13bedd00ae8eeb228a
Author: Sergey Vasilenko <email address hidden>
Date: Mon Mar 31 13:30:22 2014 +0400

    Setup default session backend

    Closes-bug: #1303932
    Change-Id: Iff6935caf1466acd08c9885042d5778357d745cd