Redis High Availability

Hi, brand new to REDIS. I inherited an application using REDIS. The application as it stands runs on 2 RHEL 7.9 servers with REDIS residing on both, but only running on one. The one server REDIS runs on interacts with both servers. Here’s what version I’m running:

./redis-server --version

Redis server v=5.0.5 sha=00000000:0 malloc=jemalloc-5.1.0 bits=64 build=303a395898c31a09

Based on how this is running, when we patch these servers, we can’t do it without an outage. How can I set redis up in a way that I could take down one server at a time without sustaining an outage?

Note that I’m in the middle of Intro to Redis Structures and am signed up for Running Redis at Scale, but it doesn’t start until August 3 and my team is interested in getting this going ASAP. Thanks!

It appears this isn’t a very active forum, so I’ll start working on my own answer, lol. Looking at REDIS Cluster vs. REDIS Sentinel. I have only 2 boxes to work with in each environment (2 test environments and 1 prod environment). I don’t see any scenario in Sentinel where 2 boxes will work. All described case scenarios show at least 3 boxes to fulfill quorum, 1 goes down so it takes 2 to acknowledge that and establish moving the master sentinel.

The scale class starts today which should be helpful… I’ll post more as I learn more. If anyone sees me going astray, I’d appreciate redirection. Thanks!