Allow NW to process several jobs at once or if stopped on alert

Hi Bull_in_a_china_shop,

I don’t know if I understand your inquire correctly or not, but I think you mean the target sessions and max sessions attributes on the device Configurations, which is the number of backup sessions accepted by a backup device.

Here is the definition of each attribute quoted from the NetWorker Administration guide:

Target sessions:

The optimal number of target sessions per device is defined by using the Target sessions attribute of the Device resource, found in the NetWorker Console in the Devices window, on the Configuration tab of the Device property dialog box.

The Target sessions attribute allows you to set the optimal number of backup sessions accepted by an active device. This is not a hard limit; to set a hard limit for the number of sessions to a particular device, use the Max sessions attribute, described below.

Instead of a hard limit, the Target sessions attribute aids in load balancing for devices by determining when the NetWorker software should begin writing save streams to another device:

- If a device is already receiving the number of backup sessions determined by the target sessions value, the NetWorker server uses the next underutilized device for the backups.

- If all available devices are receiving the number of backup sessions determined by their target sessions value, the NetWorker server overrides the set value and uses the device with the least activity for the next backup session.

Because it is often more efficient for the NetWorker server to multiplex multiple save sets to the same device, rather than write each save set to a separate device, the NetWorker server attempts to assign to each device a number of save sets, up to the value of target sessions, before assigning a save set to another device.

Note: When the NetWorker software assesses how many devices need to be involved in multiple savestreams assignments with the same storage node, the device with the lowest target session value is used as a reference. It does not make a difference if the device with the lowest target session value is associated with a different pool than the incoming savestreams.

Max sessions

The maximum number of target sessions per device is defined by using the Max sessions attribute of the Device resource, found in the NetWorker Console in the Devices window, on the Configuration tab of the Device property dialog. This attribute defines the maximum number of save sessions for a device. Its value is never less than the target sessions value.

So set the Target Sessions parameter to be equivalent, or higher, to the total number of savesets expected to back up to that device. Also, make sure the "Max Sessions" parameter is also set to be equivalent, or higher, to the total number of savesets expected to back up to that device.

The defaults for AFTD target sessions and max device sessions are now set to the optimal values for AFTD performance:

- Device target sessions is 1

- Device max sessions is 32 to avoid disk thrashing

If required, both device target, and max session attributes can be modified to reflect values appropriate for the environment.  You can check the NetWorker admin guide; there is a table provides default target and max session values and recommendations for other device types.

Hope that this helps you,

Thanks,

Ahmed Bahaa