Which HA (High Availability) mechanisms does HDP (Ambari, Hive, Ranger, Oozie) support for the database which the services are backed by (MySQL, MariaDB & PostgreSQL)?
I've heard that MySQL HA & PostgreSQL HA are not supported, but not seen anything official.
What about Galera, Percona XtraDB Cluster, MySQL MHA, ... and/or proxy mechanisms such as ProxySQL?
Sean, I would suggest using the HA methods prescribed by the RDBMS vendor. If setup according to the DB that Hortonworks supports, then I see no reason why we wouldn't support HA for MySQL, Postgres, or Oracle with their respective services.