ElastiCache for Redis at-rest encryption is an optional feature that increases data security by encrypting data stored on disk during sync and backup or snapshot operations.
However, there are the following few constraints for data-at-rest encryption:
- It is supported only on replication groups running Redis version 3.2.6. It is not supported on clusters running Memcached.
- It is supported only for replication groups running inside VPC.
- Data-at-rest encryption is supported for replication groups running on any node type.
- During the creation of the replication group, you can define data-at-rest encryption.
- Data-at-rest encryption, once enabled, cannot be disabled.