---
name: "chio.conf"
section: "5"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/chio.conf"
---

# chio.conf(5)

medium changer configuration file

## NAME

**chio.conf** – medium changer configuration file

## DESCRIPTION

**chio.conf** is used to configure some aspects of [chio(1)](/chio/1.md), a medium changer.

The configuration file consists of a series of stanzas, one per changer, enclosed in curly braces. Empty lines and lines beginning with ‘#’ in either file are ignored.

The following aspects may be configured:

- **drive**

  Provides a non-default mapping between [st(4)](/st/4.md) devices and changer drives. For example, to map drive 0 to rst3 and drive 1 to rst2, for changer */dev/ch0*:

  ```
  changer ch0 {
  	drive rst3
  	drive rst2
  }
  ```

## FILES

- /dev/ch0

  Default changer device.

- /etc/chio.conf

  Default location for [chio(1)](/chio/1.md) configuration file.

- /etc/examples/chio.conf

  Example configuration file.

## SEE ALSO

[chio(1)](/chio/1.md), [mt(1)](/mt/1.md)

## HISTORY

The **chio.conf** file format first appeared in OpenBSD 4.0.