Description of problem: /etc/openstack-dashboard/local_settings misses SESSION_ENGINE = 'django.contrib.sessions.backends.cache' We're currently not setting up a memcache, but not setting to use it as store for sessions Horizon uses signed cookies by default for session storage. Unfortunately, this has a size limitation of 4k.
Better option is to set up a database for horizon session data, memcached and to use SESSION_ENGINE = "django.contrib.sessions.backends.cached_db"
*** Bug 1270213 has been marked as a duplicate of this bug. ***
which installer are you taking about? puppet-horizon already supports django_session_engine parameter in init.pp - I'm interested to know what change you want in OPM.
The last time (about a week ago) I used packstack, and the setting from comment#3 was not added (or something similar)
Oh, btw. it was rhos-8 that I installed for my local tests here; I don't have the environment to use osp-d.
I have proposed https://review.openstack.org/318775 with a fix. The patch uses memcache as backend and 'django.contrib.sessions.backends.cache' as SESSION_ENGINE, since setting up a database for caching would go beyond the Packstack use case.
Fixed was merged so closing this.