Configuring for multi-streaming

An advantage of using the Target method for protecting your NetWare server is the ability to multi-stream data. Multi-streaming is the sending of multiple streams of data from the NetWare Client to the NetBackup server. Multiple data streams can reduce the backup time for large backups. Because the backup streams are completely independent, multiple data streams also provide a form of checkpoint restart. A single failure only terminates a single stream, and NetBackup can restart the failed stream without starting the others, improving retry time when a backup failure occurs.

To multi-stream data using the NetWare Client, though, you must do the following:

•Have multiple targets configured, one for each volume.

•Use a policy that has Allow multiple data streams enabled.

•Configure the NetBackup master server's Global NetBackup Attributes to allow more than one Maximum jobs per client.

•Use a storage unit that has Maximum concurrent drives used for backup or Maximum multiplexing per drive set higher than 1.

For information about creating targets, see Defining targets to back up.

To enable multiple data streams for a policy

  • From the NetBackup master server's administration console, create a new policy or edit an existing policy, following the steps described in the NetBackup Administrator's Guide, Volume I.
  • On the policy's Attributes tab, ensure Allow multiple data streams is enabled.

To enable multiplexing for storage units

  • From the NetBackup master server's administration console, follow the steps described in the NetBackup Administrator's Guide, Volume I for creating or modifying a storage unit.
  • If the Storage Unit Type is Media Manager, perform the following steps:

a.Ensure the Maximum concurrent drives used for backup or Maximum multiplexing per drive on the Change storage unit dialog is set higher than 1.

Setting this option to 1, which is the default, disables multiplexing and allows only one backup job at a time per drive. Specifying a maximum greater than 1 allows NetBackup to send concurrent, multiple backups from one or several clients to a single drive and multiplexes the backups onto the media.

b.Set the Media multiplexing option on the Change schedule dialog to higher than 1.

  • If the Storage Unit Type is Disk, ensure the Maximum concurrent jobs option on the Change storage unit dialog is set to higher than 1.

To allow multiple jobs per client

  • From the NetBackup master server's administration console, bring up the NetBackup master server Properties pages, following the steps described in the NetBackup Administrator's Guide, Volume I.
  • Select Global NetBackup Attributes, and then set the Maximum jobs per client to between be 2 and 8.

Maximum jobs per client specifies the maximum number of backup and archive jobs that NetBackup clients can perform concurrently. NetBackup can process concurrent backup jobs on the same client using different policies only if one of the following is true:

•More than one storage unit is available.

•One of the available storage units can perform more than one backup at a time.


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