The backups feature of the Oracle Cloud Infrastructure Block Volume service lets you make a point-intime snapshot of the data on a block volume.These backups can then be restored to new volumes either immediately after a backup or at a later time that you choose.
You can copy block volume backups between regions using the Console, command line interface (CLI), SDKs, or REST APIs.
To copy volume backups between regions, you must have permission to read and copy volume backups in the source region, and permission to create volume backups in the destination region.
to do all things with block storage volumes, volume backups, and volume groups in all compartments with the exception of copying volume backups across regions.
Allow group VolumeAdmins to manage volume-family in tenancy
The aggregate resource type volume-family does not include the VOLUME_BACKUP_COPY permission, so to enable copying volume backups across regions you need to ensure that you include the third statement in that policy, which is:
Allow group VolumeAdmins to use volume-backups in tenancy where request.permission='VOLUME _BACKUP_COPY'

Explanation
You can move a compartment to a different parent compartment within the same tenancy. When you move a compartment, all its contents (subcom partments and resources) are moved with it.
After you move a compartment to a new parent compartment, the access policies of the new parent take effect and the policies of the previous parent no longer apply. Before you move a compartment, ensure that:
- You are aware of the policies that govern access to the compartment in its current position.
- You are aware of the polices in the new parent compartment that will take effect when you move the compartment.
1- Policy that defined in root compartment: Allow group admins to read subnets in compartment Finance:A:X you move compartment X from Finance:A to HR:C. The policy that governs compartment X is attached to the shared parent, root compartment. When the compartment X is moved, the policy statement is automatically updated by the IAM service to specify the new compartment location.
The policy
Allow group admins to read subnets in compartment Finance:A:X
is updated to Allow group admins to read subnets in compartment HR:C:X
so the admins group will have the same access after the compartment X is moved
2- Policy that defined in compartment A: Allow group networkadmins to manage subnets in compartment X you move compartment X from Finance:A to HR:C. However, the policy that governs compartment X here is attached directly to the A compartment. When the compartment is moved, the policy is not automatically updated. The policy that specifies compartment X is no longer valid and must be manually removed. Group networkadmins no longer has access to compartment X in its new location under HR:C.
Unless another existing policy grants access to group networkadmins , you must create a new policy to allow networkadmins to continue to manage buckets in compartment X.

Explanation
Autonomous Database is an Oracle Managed and Secure environment.
A physical database can't simply be migrated to autonomous because:
- Database must be converted to PDB, upgraded to 19c, and encrypted
- Any changes to Oracle shipped privileges, stored procedures or views must be removed
- All legacy structures and unsupported features must be removed (e.g. legacy LOBs) GoldenGate replication can be used to keep database online during migration