4.The BSM starts Disk Agents (DAs) for each disk to be backed up in parallel. The actual number of Disk Agents started depends on the concurrency of Disk Agents configured in the backup specification. This is the number of Disk Agents that can be started to send data in parallel to a Media Agent, thus allowing a device to stream.
5.Disk Agents read data from disks and send it to the Media Agents that write data to media.
In a backup session with object mirroring, Media Agents used for writing mirrored objects are
6.The BSM monitors the progress of the session and starts new Disk Agents and new Media Agents as necessary.
7.When the backup session is completed, the BSM closes the session.
Figure 63 Backup session information flow (1)
How many sessions can run concurrently?
A number of backup sessions can run in the cell at the same time. This number is limited by resources in the cell, such as the availability of devices and the configuration of the Cell Manager, for instance, processor speed, main memory size, and similar.
222 | How Data Protector operates |