Multiple Data Streams

The connections for multiple jobs (streams) started as a result of using Allow multiple data streams are the same as for other backups. That is, NetBackup creates a separate set of connections for each job.

If auto-discover streaming mode is enabled (for example, by using the ALL_LOCAL_DRIVES directive), the master server opens an additional connection to bpcd on each client in order to obtain the required number of streams. This connection is to either a reserved or nonreserved port, depending on what the client is configured to accept for bpcd. The connect back is to the port specified during the bpcd connection and also is reserved or nonreserved according to what was used for bpcd.

The next two figures show backup connections both with and without multiplexing. Multiplexing results in an additional connect back for each job in the same way as when Allow multiple data streams is not used.

Connections for Multiple Data Streams - Without Multiplexing

Connections for Multiple Data Streams - With Multiplexing

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