http://dacxzjk3kq5mmepbdd3ai2ifynlzxsnpl2cnkfhridqfywihrfftapid.onion/help/administration/redis/replication_and_failover.md
Before diving into the details of setting up Redis and Redis Sentinel for a
replicated topology, make sure you read this document once as a whole to better
understand how the components are tied together.
You need at least 3 independent machines: physical, or VMs running into
distinct physical machines. It is essential that all primary and replica Redis
instances run in different machines.