So you are not doing a VM backup using VE integration.
In this case, It does not matter for Data Protector Oracle Integration, that where is the backup media. Your Backup media (Device) can be disk/tape, which is Local or connected via SAN. This Device is configured in Backup specification.
Backup process:
The Data Protector Oracle Integration agent (ob2rman.pl) works with RMAN to manage all aspects Backup and Recovery operations of the Oracle target database.
The Oracle Server processes initialize the backup through Oracle MML(Media Management library), which establishes a connection to the Data Protector Backup Session Manager. The Backup Session Manager starts the General Media Agent, sets up a connection between MML and the General Media Agent, and then monitors the backup process.
Then Oracle Server processes read the data from the disks and send it to the backup devices through MML and the General Media Agent.
The Data Protector General Media Agent writes data to the backup devices.
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In case of VM backup, for SAN, you need to present the datastore where Oracle is installed, to the Backup host also.