The patching is done every quarter. Although there is no order dependency between
EI/AVM/ACD, it is preferred to patch in the sequence EI, AVM, and then ACD.
Oracle schedules and performs all patching and other maintenance operations on all
dedicated Exadata infrastructure resources. You can also specify when such maintenance
operations can occur, and what kind of patching is performed.
In general, Oracle schedules and performs entire fleet maintenance spread
throughout each quarter. You can let Oracle handle maintenance scheduling, or you can
set a specific maintenance window when Oracle can begin maintenance operations. You set
this maintenance window at the Autonomous Exadata Infrastructure level, and it applies
to all Autonomous Container Databases and Autonomous Databases created in the Autonomous
Exadata Infrastructure resource as well as to the resource itself.
Additionally, you can set a maintenance window for each individual
Autonomous Container Database, thereby setting the window for all of its contained
Autonomous Databases.
Note
Oracle recommends that you set a maintenance window for at least Exadata
Infrastructure resources. Doing so will prevent maintenance operations from
occurring at times that would be disruptive to regular database operations.
You can set the maintenance window for an Exadata Infrastructure and
Autonomous Container Database resources when you create them or you can set or change it
later. Once a maintenance activity is scheduled based on the maintenance window you set,
you can manage the actual timing of the activity, even to the point of changing the
patch version, applying the patch immediately, or skipping the activity.
One standard maintenance operation is to apply database software patches to your
Autonomous Container Databases and, by extension, the Autonomous Databases created in
them. By default, Oracle applies quarterly Release Updates (RUs). Currently, the Release
Update Revision (RUR) maintenance type is not supported.
To help you decide whether to have Oracle apply RUs or RURs to a given Autonomous
Container Database, see My Oracle Support Note 2285040.1.