Cross region replication of Redis Docker container data
You don't mention orchestration, are you planning to implement all by your own configuration on top of Ubuntu?

I recommend you that take a look at Kubernetes and StatefulSet workloads

https://kubernetes.io/docs/concepts/workloads/controllers/statefulset/

You can use Ubuntu as your host to accomplish your needs, but in my experience, you can only need to define correctly your workload and open the right ports to communicate and with the kubernetes integration on different providers you have the persistent volume easy to manage.

Also, I recommend you to review Helm and you have a redis-ha chart ready

https://github.com/helm/charts/tree/master/stable/redis-ha