nvmf_tcp(4)

nvmf_tcp4

Tcp transport for nvm express over fabrics

Usage

To compile the module into the kernel, place the following line in the kernel configuration file:

device nvmf_tcp

Alternatively, to load the module at boot time, place the following line in loader.conf(5):

nvmf_tcp_load="YES"

Overview

The nvmf_tcp module implements the software TCP/IP transport for NVM Express over Fabrics. It can be used by either the in-kernel NVMeoF host driver or controller.

Sysctl variables

The following variables are available as both sysctl(8) variables and loader(8) tunables:

kern.nvmf.tcp.max_transmit_data

The maximum data payload size of C2H_DATA and H2C_DATA PDUs. A remote controller may enforce a lower limit on the size of H2C_DATA PDUs via the MAXH2CDATA parameter. The default size is 256 kilobytes.

Releases

3 releases since FreeBSD 15.0-RELEASE; the text changed 1 time.

  1. 15.0
  2. 15.1–16.0

History

The nvmf_tcp module first appeared in FreeBSD 15.0.

Authors

The nvmf_tcp module was developed by John Baldwin ⟨[email protected]⟩ under sponsorship from Chelsio Communications, Inc.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.