There was an issue with the backend service pulp3: Pulp redis connection issue at https://sysadmin.foreman.com/pulp/api/v3

[lumarel]

Could you please have a look in the /etc/foreman-installer/scenarios.d/katello-answers.yaml file please and check that the pulpcore_cache_enabled parameter is set to true?

Ref:

Upgrade issue to 4.4.1 - Internal Server Error (and a notice about 4.5 RC2)

@lumarel In /etc/pulp/settings.py check the CACHE_ENABLED setting. After upgrading to 4.5-RC2, I had the same redis issue. CACHE_ENABLED was set to False. There’s a note in the pulp documentation stating it should be set to True, however. I changed the setting to True and restarted the pulpcore services. After that, repo syncing starting working again. After around digging in foreman-installer, I found that pulpcore_cache_enabled was set to false in /etc/foreman-installer/scenarios.d/foreman-…

If it is set to false, set it to true and rerun the foreman-installer