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IF_NTB(4)		 BSD Kernel Interfaces Manual		     IF_NTB(4)

NAME
     if_ntb -- Virtual Ethernet	interface for Non-Transparent Bridges

SYNOPSIS
     To	compile	this driver into your kernel, place the	following lines	in
     your kernel configuration file:

	   device ntb
	   device ntb_transport
	   device if_ntb

     Or, to load the driver as a module	at boot, place the following line in
     loader.conf(5):

	   if_ntb_load="YES"

     The following tunables are	settable from the loader(8):

     hw.if_ntb.num_queues
     Limits maximal number of queues per interface.  Default is	unlimited.

DESCRIPTION
     The if_ntb	driver attaches	on top of the ntb_transport(4) driver to uti-
     lize one or more of its packet queues to create virtual Ethernet network
     interface between the systems.  Typical MTU for the interface is about
     64KB to reduce overhead.  Default MAC address for the interface is	ran-
     domly generated.

     The if_ntb	driver does not	implement any real hardware offload, but since
     PCIe link is protected by CRC32, in some situations it may	be possible to
     save some CPU cycles by enabling fake checksum offload on both link sides
     via setting rxcsum	and txcsum interface options.

SEE ALSO
     ntb_transport(4)

AUTHORS
     The if_ntb	driver was developed by	Intel and originally written by	Carl
     Delsey <carl@FreeBSD.org>.	 Later improvements were done by Conrad	E.
     Meyer <cem@FreeBSD.org> and Alexander Motin <mav@FreeBSD.org>.

BUGS
     Linux supports only one queue per interface, so manual configuration may
     be	required for compatibility.

BSD			       September 2, 2017			   BSD

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | AUTHORS | BUGS

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