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33 .Nd Virtual Ethernet interface for Non-Transparent Bridges
35 To compile this driver into your kernel,
36 place the following lines in your kernel configuration file:
37 .Bd -ragged -offset indent
39 .Cd "device ntb_transport"
43 Or, to load the driver as a module at boot, place the following line in
45 .Bd -literal -offset indent
49 The following tunables are settable from the
52 .It Va hw.if_ntb.num_queues
53 Limits maximal number of queues per interface.
59 driver attaches on top of the
61 driver to utilize one or more of its packet queues to create virtual
62 Ethernet network interface between the systems.
63 Typical MTU for the interface is about 64KB to reduce overhead.
64 Default MAC address for the interface is randomly generated.
68 driver does not implement any real hardware offload, but since PCIe link is
69 protected by CRC32, in some situations it may be possible to save some CPU
70 cycles by enabling fake checksum offload on both link sides via setting
81 driver was developed by Intel and originally written by
82 .An Carl Delsey Aq Mt carl@FreeBSD.org .
83 Later improvements were done by
84 .An Conrad E. Meyer Aq Mt cem@FreeBSD.org
86 .An Alexander Motin Aq Mt mav@FreeBSD.org .
88 Linux supports only one queue per interface, so manual configuration
89 may be required for compatibility.