---
name: "nvmf_tcp"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/nvmf_tcp"
---

# nvmf\_tcp(4)

TCP transport for NVM Express over Fabrics

## NAME

**nvmf\_tcp** – TCP transport for NVM Express over Fabrics

## SYNOPSIS

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)](/loader.conf/5.md):

```
nvmf_tcp_load="YES"
```

## DESCRIPTION

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)](/sysctl/8.md) variables and [loader(8)](/loader/8.md) 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.

## SEE ALSO

[nvmf(4)](/nvmf/4.md), [nvmft(4)](/nvmft/4.md)

## HISTORY

The **nvmf\_tcp** module first appeared in FreeBSD 15.0.

## AUTHORS

The **nvmf\_tcp** module was developed by John Baldwin ⟨*jhb@FreeBSD.org*⟩ under sponsorship from Chelsio Communications, Inc.