Queuing of backup sessions

Timeout

When a backup session is started, Data Protector tries to allocate all needed resources, such as devices. The session is queued until the required minimum resources are available. If the resources are still unavailable after the timeout, the session is aborted. The timeout period can be set using the SmWaitForDevice global option.

Optimizing the load

To optimize the load on the Cell Manager, Data Protector can, by default, start up to five backup sessions at the same time. The default value can be modified in the global options file. If more are scheduled at the same time, the extra sessions are queued and started subsequently as others are finished.

Mount requests in backup sessions

What is a mount request?

A mount request in a backup session appears when Data Protector needs a new medium for backup and the medium is not available.

Data Protector issues a mount request for one of the following reasons:

Issuing a mount request

There is not enough space on the backup media and there are no new media available.

Data Protector media allocation policy for backup requires a medium that is not available in the device.

The order of media used for backup is defined in the pre allocation list and media are not available in this order.

For more information, see Adding data to media during backup sessions” on page 148 and Selecting media for backups ” on page 147.

Responding to a mount request

Responding to a mount request includes providing the required media and telling Data Protector to proceed with the backup.

Data Protector allows you to configure what happens when a mount request is issued:

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How Data Protector operates