I'm planning to run Odoo on AWS. I need to have real time replication so that we have fail-over. EC2 instances would just have Odoo running and would be put under ELB. RDS (multi - az) postgres would be the database and EFS storage would host all uploads/dynamic files. This would work fine except if there is a region wide outage.
I would like to get suggestions on having a fail-over across regions. I guess I would be using Route 53 and EC2 instance in different regions. Since EFS does not support it I assume I have to use something like Gluster. RDS supports read-replicas across regions. But can we use that as the primary database automatically without doing anything in the AWS console (i.e human intervention). Also how does fail-over work exactly in this case? Will there be any downtime?