Oracle Real Application Clusters (Oracle RAC) is the only solution to build an active – active cluster using shared storage for your Oracle database. Up to Oracle 18c RAC is available as a feature within Standard Edition 2 (SE2) and comes as an extra-cost option with Enterprise Edition.
Oracle RAC typically protects your database against node failure. It does not protect your database against storage failure (it is shared by two nodes) or against human errors.
As from Oracle 19c (corresponding with 18.104.22.168 in the old version numbering!), Oracle announced that RAC will no longer be supported / allowed within Standard Edition 2. It will still be available as an extra-cost option within Enterprise Edition.
Removing Oracle RAC from Standard Edition 2 brings customers using RAC on Standard Edition 2 a
new challenge: configure a high available database environment without RAC.
Oracle and high availability
Let us have a look at what the options are. The first questions you should ask yourself:
– What are your business requirements?
– Why did you choose RAC on SE2? To perform patching operations online? To protect against
what kind of failure (instance, host failure etc)?
In the paper we describe six alternative solutions, their pros and their cons:
- Configure active – passive cluster using Oracle clusterware
- Configure active – passive cluster using operating system clustering
- Configure active – passive cluster using Oracle VM
- Move to the Oracle cloud
- Configure disaster recovery using Dbvisit Standby
- Upgrade to Enterprise Edition
For more information see My Oracle Support Note 2504078.1: Desupport of Oracle Real Application Clusters (RAC) with Oracle Database Standard Edition 19c
This news will certainly lead to smaller companies to evaluate whether to migrate their databases from Oracle to open source solutions, such as Mariadb, Postgresql, which partially support Oracle syntax and consequently migration will be easier.
For those wishing to learn more :
Mariadb : https://mariadb.com/kb/en/sql_modeoracle-from-mariadb-103
Postgresql : https://wiki.postgresql.org/wiki/Oracle_to_Postgres_Conversion