Amazon Aurora and Similar Scalable, Centralized Database Engines

The 1:1 relationship between MariaDB and a mailbox server should be removed. It creates a performance choke point, is a single point of failure, and increases costs by requiring us to host mailbox servers with large amounts of RAM, just so we can have innodb_buffer_pool_size large enough.

In the latest Carbonio: https://docs.zextras.com/carbonio/html/architecture.html MariaDB has been replaced with Postgres, and all mailbox servers in a pool can use a remote Postgres server.

Amazon Web Services offers Aurora, a scalable database-as-a-service offering: https://aws.amazon.com/rds/aurora/

If I could specify an IP address for a MariaDB database cluster, then I could reduce the sizes of my mailbox server instances by eliminating the CPUs and RAM needed just for MariaDB. A preliminary analysis indicates these cost savings far exceed the marginal cost for an Aurora implementation.

With blobs stored on external storage and MariaDB data stored externally in a cluster, other than mailbox indexes (and backup data) there is not much user data left to host on a mailbox server. This should simplify disaster recovery longer term as well. Please consider. Thanks!