Sometimes people ask about certain Oracle High Availability features and whether they exist in PostgreSQL.
In most cases, very similar features exist. The reason for the similarity is that PostgreSQL and Oracle have very similar architectures and so the mechanisms to protect data have also developed along the same lines.
For example, Oracle Data Guard is streaming replication of the transaction log, so is very similar in concept to physical streaming replication in PostgreSQL. Active Data Guard is where Oracle users can run queries on a standby server, which again is similar in concept to Hot Standby.
Oracle RAC? You don’t really need Oracle RAC. Or at least qualified Oracle experts tell me so and my own hands on experience confirms that. Not least because disaster recovery for RAC needs to be provided by Data Guard (so why not just use Data Guard). So there is no equivalaent of RAC in the world of PostgreSQL. (Phew!)
Looking for RMAN? There is a backup and recovery tool called Barman which takes advantage of the built-in features for Point in Time Recovery.
There’s more detail there also but a fully detailed explanation is something to discuss as part of technical training or a migration project. The main message is that PostgreSQL supports HA with a range of detailed features that have been in production for many years.