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Network Block Device (NBD)

NBD is a simple protocol for Linux to export a block device across a network.


The NBD protocol was devised and written by Pavel Machek in 1998. Since the protocol is so simple (see below), there hasn't been any need to modify it since, and the protocol is still very much like the original version.

Protocol dependencies

Example traffic


The NBD dissector is fully functional for everything after the initial negotiation phase.

Preference Settings

(XXX add links to preference settings affecting how PROTO is dissected).

Example capture file

XXX - Add a simple example capture file to the SampleCaptures page and link from here (see below). Keep this file short, it's also a good idea to gzip it to make it even smaller, as Wireshark can open gzipped files automatically.

Display Filter

A complete list of NBD display filter fields can be found in the display filter reference

Capture Filter

You cannot directly filter NBD protocols while capturing. However, if you know the TCP port used (see above), you can filter on that one.


NBD (last edited 2011-03-17 19:27:04 by BillMeier)