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IF_NTB(4) FreeBSD 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
utilize 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
randomly 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.
FreeBSD 14.0-RELEASE-p11 September 2, 2017 FreeBSD 14.0-RELEASE-p11