What protocol does Netbackup 8.3.x use to transfer data from Windows Server with MS-Windows policy?

[SDF4]

Is it Windows SMB, or is Netbackup using its own protocol? I know this is a really basic question but I haven't been able to find out from the documentation or google.

The background is I've come into an environment using Netbackup and currently having problems with slow backups. I want to better understand how Netbackup works so I have an idea what to look at. Ie, there would be no point me tinkering with SMB if it turns out Netbackup uses something else!

[Nicolai · Accepted solution]

Netbackup uses a customized version of the unix command TAR (in the bpbkar process) to create a bit stream over the network using tcp/1556, or 13724 or 13782. No SMB involved at all

Process flow in : https://www.veritas.com/support/en_US/doc/86063237-127664549-0/v109483729-127664549

You may search VOX for performance tuning hint and tricks. But first check NUMBER_DATA_BUFFERS and make sure the value is 256 or larger and not the default 64. You can see current value of NUMBER_DATA_BUFFERS in the activity monitor for each backup job (not control job).