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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
41 Or, to load the driver as a module at boot, place the following line in
43 .Bd -literal -offset indent
47 The following tunables are settable from the
50 .It Va hw.if_ntb.num_queues
51 Number of transport queues to use per interface.
57 driver attaches on top of the
59 driver to utilize its resources to create virtual Ethernet interface between
61 Interface capabilities depend on the underlying transport.
62 Typical MTU is about 64KB to reduce overhead.
63 By default one queue is used, but more may be configured.
64 The MAC address for 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.