Hello!
Yes, we got it running with Redis server, although we deployed only a single-instance setup. Did not really bother with cluster at this stage. Running a couple of months now with no LibreNMS-related issues (meaning, we have problems, but they are network-related and have nothing to do with LibreNMS itself).
We also have faced multiple master instances to be present in poller cluster as reported by LibreNMS, although it does not affect production environment and I’m pretty much happy with that. We have also edited the source of poller, full story available here.
Here is our Redis config portion sample:
REDIS_HOST=10.10.10.10
REDIS_DB=0
REDIS_PASSWORD=
REDIS_PORT=6379