Hi
Apparently, in 3.11.0 and further versions the php-redis module is mandatory as Sam told me in a support ticket.
I have checked now with our sys admin, for RHEL it seems like redis is only available in the community-driven epel-Repository and not the official redhat repository. Due to restrictions we should only use the redhat repositories… Is there any chance that we could proceed without installing redis? We won’t use it anyway in our local installation.
Thanks
Fabian
I’d be interested in more info here too…
when I installed the most recent upgrade, the System Health Check says we have to manually install the Redis module, and you’re blocked from making further updates until you do -
What’s the module for? Why can’t can’t it be installed automatically? 
Hello,
Our solution is that we make it optional until you want to use redis cache. If the module is not installed it will show that redis cache option is unavailable. Should be implemented in e3.13.0. You will upload to this version with debug mode enabled, it will allow you to do this update even if there is not ok item on the system health page.
Int.ref.: https://github.com/eramba/eramba_v2/issues/3465
David, unfortunately, we can not install PHP module to your server since we do not have access to it.
Hi Sam
Great, thank you!