BNXT(4)

📦
version 15.1 · 4 versions
, in freebsd 15.1

💅 BNXT(4) — like, the Broadcom NetXtreme driver manual, but make it make sense

okay bestie, so this is the manual page for bnxt, which lives in section 4 of the Kernel Interfaces Manual (the driver section — yes, that one 🎀). Sit down, hydrate, and let's get into it.

✨ NAME ✨

bnxt — the Broadcom NetXtreme family Ethernet driver, and when I say family I mean it covers everything from 10Gb all the way up to 400Gb. no cap. 🔥

🌸 SYNOPSIS 🌸

So there's two ways to get this driver into your life, and it's giving "choose your own adventure".

Option A — build it straight into the kernel. Drop these lines into your kernel configuration file:

device iflib
device bnxt

Option B — load it as a module at boot time. Put this line in loader.conf(5):

if_bnxt_load="YES"

slay, that's it, that's the whole synopsis 🫶

💖 DESCRIPTION 💖

The bnxt driver provides support for PCIe NICs based on the Broadcom BCM573XX, BCM574XX, BCM575XX, and BCM576XX Ethernet controllers. iconic behavior honestly.

Want the full deets on configuring this device? Go see ifconfig(8). iykyk.

🦋 HARDWARE 🦋

Here's the part where the driver flexes its entire roster. The bnxt driver supports the following Broadcom 10Gb to 400Gb Ethernet controllers — and yes, I'm listing every single one, because we don't skip items in this house 👑

  • Broadcom BCM57301 NetXtreme-C 10Gb Ethernet Controller
  • Broadcom BCM57302 NetXtreme-C 10Gb/25Gb Ethernet Controller
  • Broadcom BCM57304 NetXtreme-C 10Gb/25Gb/40Gb/50Gb Ethernet Controller
  • Broadcom BCM57304 NetXtreme-C Ethernet Virtual Function
  • Broadcom BCM57314 NetXtreme-C Ethernet Virtual Function
  • Broadcom BCM57402 NetXtreme-E 10Gb Ethernet Controller
  • Broadcom BCM57402 NetXtreme-E Ethernet Partition
  • Broadcom BCM57404 NetXtreme-E 10Gb/25Gb Ethernet Controller
  • Broadcom BCM57404 NetXtreme-E Ethernet Virtual Function
  • Broadcom BCM57404 NetXtreme-E Partition
  • Broadcom BCM57406 NetXtreme-E 10GBASE-T Ethernet Controller
  • Broadcom BCM57406 NetXtreme-E Partition
  • Broadcom BCM57407 NetXtreme-E 10GBase-T Ethernet Controller
  • Broadcom BCM57407 NetXtreme-E 25Gb Ethernet Controller
  • Broadcom BCM57407 NetXtreme-E Partition
  • Broadcom BCM57412 NetXtreme-E Partition
  • Broadcom BCM57414 NetXtreme-E Ethernet Virtual Function
  • Broadcom BCM57414 NetXtreme-E Partition
  • Broadcom BCM57416 NetXtreme-E Partition
  • Broadcom BCM57417 NetXtreme-E Ethernet Partition
  • Broadcom BCM57454 NetXtreme-E 10Gb/25Gb/40Gb/50Gb/100Gb Ethernet
  • Broadcom BCM57502 NetXtreme-E 10Gb/25Gb/50Gb Ethernet
  • Broadcom N425 BCM57504 NetXtreme-E 10Gb/25Gb Ethernet
  • Broadcom P425 BCM57504 NetXtreme-E 10Gb/25Gb Ethernet
  • Broadcom N1100 BCM57504 NetXtreme-E 10Gb/25Gb/50Gb/100Gb Ethernet
  • Broadcom N2100 BCM57508 Thor 10Gb/25Gb/50Gb/100Gb Ethernet
  • Broadcom P2100 BCM57508 Thor 10Gb/25Gb/50Gb/100Gb Ethernet
  • Broadcom N2200 BCM57608 Thor 2 10Gb/25Gb/50Gb/100Gb/200Gb Ethernet
  • Broadcom P2200 BCM57608 Thor 2 10Gb/25Gb/50Gb/100Gb/200Gb Ethernet
  • Broadcom N1400 BCM57608 Thor 2 25Gb/50Gb/100Gb/200Gb/400Gb Ethernet
  • Broadcom P1400 BCM57608 Thor 2 25Gb/50Gb/100Gb/200Gb/400Gb Ethernet

🎀 SYSCTL VARIABLES 🎀

⭐ the "set these BEFORE you load the driver" girlies

These variables must be set before loading the driver, either via loader.conf(5) or through the use of kenv(1). They're actually provided by the iflib(4) framework, so honestly they might be better documented over there. just saying 💅

  • dev.bnxt.X.iflib.override_nrxds — Override the number of RX descriptors for each queue. The value is a comma separated list of three positive integers: the size of the completion ring, the size of the receive ring, and the size of the aggregation ring respectively. The completion ring should be at least the size of the aggregation ring plus four times the size of the receive ring. These numbers must be powers of two, and zero means to use the default. Defaults to 0,0,0.
  • dev.bnxt.X.iflib.override_ntxds — Override the number of TX descriptors for each queue. The value is a comma separated list of two positive integers: the size of the completion ring, and the size of the transmit ring respectively. The completion ring should be at least twice the size of the transmit ring. These numbers must be powers of two, and zero means to use the default. Defaults to 0,0.
  • dev.bnxt.X.iflib.override_qs_enable — When set, this allows the number of transmit and receive queues to be different. If it's not set, the lower of the number of TX or RX queues will be used for both. 🫶
  • dev.bnxt.X.iflib.override_nrxqs — Set the number of RX queues. If zero, the number of RX queues is derived from the number of cores on the socket connected to the controller. Defaults to 0.
  • dev.bnxt.X.iflib.override_ntxqs — Set the number of TX queues. If zero, the number of TX queues is derived from the number of cores on the socket connected to the controller.

🌈 the "change me whenever, bestie" sysctls

These sysctl(8) variables can be changed at any time:

  • dev.bnxt.X.vlan_only — Require that incoming frames must have a VLAN tag on them that matches one that's configured for the NIC. Normally, both frames that have a matching VLAN tag and frames that have no VLAN tag are accepted. Defaults to 0.
  • dev.bnxt.X.vlan_strip — When non-zero, the NIC strips VLAN tags on receive. Defaults to 0.
  • dev.bnxt.X.rx_stall — Enable buffering rather than dropping frames when there are no available host RX buffers for DMA. Defaults to 0. (buffering > dropping, lowkey)
  • dev.bnxt.X.rss_type — Comma-separated list of RSS hash types to support. Default is all types. Defaults to ipv4,tcp_ipv4,udp_ipv4,ipv6,tcp_ipv6,udp_ipv6.
  • dev.bnxt.X.rss_key — Current RSS key. Defaults to a randomly generated value which is generated for each device during attach. ✨randomized✨
  • dev.bnxt.X.ver.hwrm_min_ver — Minimum HWRM (HardWare Resource Manager) firmware API to support. If the firmware implements an older version, a warning will be printed, and the firmware should be upgraded. Defaults to 1.2.2.

🔒 the read-only ones (look, don't touch, bestie)

These sysctl(8) variables are read-only:

  • dev.bnxt.X.if_name — Current interface name of the device. This will normally be bnxtX, but this can be changed using ifconfig name. This sysctl allows correlating an interface with a child of dev.bnxt.
  • dev.bnxt.X.nvram.* — Information about the NVRAM device which contains the device firmware.
  • dev.bnxt.X.ver.* — Version-related information about the device and firmware:
    • dev.bnxt.X.ver.hwrm_if — Supported HWRM API version of the currently running firmware.
    • dev.bnxt.X.ver.driver_hwrm_if — HWRM API version the driver was built to support.
  • dev.bnxt.X.hwstats.* — Per-queue statistics tracked by the hardware.
  • dev.bnxt.X.hwstats.port_stats.* — Per-port statistics tracked by the hardware.
  • dev.bnxt.X.hwstats.rxq0.drop_pkts — Number of packets dropped by hardware on queue zero. This number might seem high, but the count includes packets dropped due to incorrect destination MAC, unsubscribed multicast address, and other normal reasons to ignore Ethernet frames. so don't panic 😭
  • dev.bnxt.X.hwstats.rxq0.tpa_* — statistics related to HW LRO.
  • dev.bnxt.X.hw_lro.* — Enable / Disable HW LRO feature. Defaults to disable. > Enabling HW LRO could cause issues when forwarding is enabled on host. you've been warned 💀
  • dev.bnxt.X.fc — Enable / Disable Flow Control feature. Defaults to Enable

💀 DIAGNOSTICS 💀

When things go sideways, you get these bad boys. Read them, don't just scroll past 🫶

bnxt%d: %s command returned %s error.

Device firmware rejected a command from the driver. There might be a driver/firmware HWRM API mismatch.

bnxt%d: Timeout sending %s (timeout: %d) seq %d

Device firmware unresponsive. A PCI device reset is likely needed. 😭

bnxt%d: Timeout sending %s (timeout: %d) msg {0x%x 0x%x} len:%d v: %d

Partial firmware response. A PCI device reset is likely needed.

As of this writing, the system must be rebooted to initiate a PCI device reset. no soft fix for this one, bestie, you're rebooting. 💅

🌟 SEE ALSO 🌟

altq(4), arp(4), iflib(4), netintro(4), ng_ether(4), vlan(4), ifconfig(8)

🎀 HISTORY 🎀

The bnxt device driver first appeared in FreeBSD 11.1. throwback era fr fr 🦋

👑 AUTHORS 👑

The bnxt driver was written by Jack Vogel <jfvogel@gmail.com> and Stephen Hurd <shurd@freebsd.org>, and is currently maintained by Broadcom Limited <freebsd.pdl@broadcom.com>.

okay that's the whole page, you ate that 💖 This cutie came from the Debian build of the page, dated December 10, 2025, and it's filed under BNXT(4). mwah, go configure some NICs 🎀✨

📦 where this page comes from
  • freebsd 15.1: base 15.1
  • Copyright (c) 2016 Broadcom, All Rights Reserved
  • 💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms