Copyright (c) 2016 Alexander Motin <mav@FreeBSD.org>
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$FreeBSD: stable/11/share/man/man4/if_ntb.4 323453 2017-09-11 18:48:09Z mav $
.Dd September 2, 2017 .Dt IF_NTB 4 .Os .Sh NAME .Nm if_ntb .Nd Virtual Ethernet interface for Non-Transparent Bridges .Sh SYNOPSIS To compile this driver into your kernel, place the following lines in your kernel configuration file: d -ragged -offset indent .Cd "device ntb" .Cd "device ntb_transport" .Cd "device if_ntb" .Ed
p Or, to load the driver as a module at boot, place the following line in .Xr loader.conf 5 : d -literal -offset indent if_ntb_load="YES" .Ed
p The following tunables are settable from the .Xr loader 8 : l -ohang t Va hw.if_ntb.num_queues Limits maximal number of queues per interface. Default is unlimited. .El .Sh DESCRIPTION The .Nm driver attaches on top of the .Xr 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.
p The .Nm 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 .Cm rxcsum and .Cm txcsum interface options. .Sh SEE ALSO .Xr ntb_transport 4 .Sh AUTHORS .An -nosplit The .Nm driver was developed by Intel and originally written by .An Carl Delsey Aq Mt carl@FreeBSD.org . Later improvements were done by .An Conrad E. Meyer Aq Mt cem@FreeBSD.org and .An Alexander Motin Aq Mt mav@FreeBSD.org . .Sh BUGS Linux supports only one queue per interface, so manual configuration may be required for compatibility.