---
name: "rdsetroot"
section: "8"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/rdsetroot"
---

# rdsetroot(8)

insert disk image into RAMDISK kernel

## NAME

**rdsetroot** – insert disk image into RAMDISK kernel

## SYNOPSIS

**rdsetroot** **-s** *kernel*

**rdsetroot** \[**-dx**\] *kernel* \[*disk.fs*\]

## DESCRIPTION

The **rdsetroot** utility inserts the file *disk.fs* into the reserved space inside a RAMDISK kernel. If *disk.fs* is not specified, **rdsetroot** reads from standard input.

The options are as follows:

- **-d**

  Debug.

- **-s**

  Print the size in bytes of the reserved space in the RAMDISK kernel. No insertion or extraction is attempted.

- **-x**

  Rather than inserting, extract the *disk.fs* image. If *disk.fs* is not specified, **rdsetroot** writes to standard output. The disk can be made accessible using [vnconfig(8)](/vnconfig/8.md), filesystems can be manipulated, and finally re-inserted into the RAMDISK kernel.

## SEE ALSO

[config(8)](/config/8.md), [disklabel(8)](/disklabel/8.md), [vnconfig(8)](/vnconfig/8.md)