With the new Aerospike 3.5.14 comes the shadow device functionality on EC2 as read here: http://www.aerospike.com/docs/deploy_guides/aws/recommendations/
I am still unclear as to why one would want that. We are already using fast direct-attached instance store SSD with a replication factor of 2. We don’t use EBS. If we loose a node then the cluster rebalances itself.
Unless you would recommend the shadow EBS when using a replication factor of 1 and allowing downtime on some part of the data when a node goes down? A replication factor of 1 would decrease cost as we would need to run less nodes. The tradeoff would be some downtime on part of the data set when the node goes down but since the data would be copied to the shadow EBS then there would be no data loss once we restore the node and reattach the volume?