---
name: "mount_vnd"
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/mount_vnd"
---

# mount\_vnd(8)

mount vnode disks

## NAME

**mount\_vnd** – mount vnode disks

## SYNOPSIS

**mount\_vnd** \[**-k**\] \[**-K** *rounds*\] \[**-o** *options*\] \[**-S** *saltfile*\] \[**-t** *disktype*\] *image* *vnd\_dev*

## DESCRIPTION

**mount\_vnd** works similarly to [vnconfig(8)](/vnconfig/8.md), but it provides an interface that can be used by the [fstab(5)](/fstab/5.md) infrastructure, so that an *image* file can be configured to a device *vnd\_dev* while booting.

For [fstab(5)](/fstab/5.md) lines with type “ffs”, the “noauto” option must be set to prevent a [mount(8)](/mount/8.md) of the FFS partitions before the necessary vnd devices are configured. Also, the “fs\_passno” field has to be set to 0 to prevent [fsck(8)](/fsck/8.md) from checking the file system for the same reasons.

**mount\_vnd** is invoked by [mount(8)](/mount/8.md) when using the following syntax:

**mount** \[options\] -t vnd *image* *vnd\_dev*

The options are as follows:

- **-K** *rounds*

  Associate an encryption key with the device. All data will be encrypted using the Blowfish cipher before it is written to the disk. The user is asked for both a passphrase and the name of a salt file. The salt file can also be specified on the command line using the **-S** option. The passphrase and salt are combined according to PKCS #5 PBKDF2 for the specified number of rounds to generate the actual key used. *rounds* is a number between 1000 and INT\_MAX. DO NOT LOSE THE SALT FILE.

- **-k**

  Associate an encryption key with the device. All data will be encrypted using the Blowfish cipher before it is written to the disk.

- **-o** *options*

  Options are specified with a **-o** flag followed by a comma separated string of options. See the [mount(8)](/mount/8.md) man page for possible options and their meanings.

  At the moment, **-o** is only here for compatibility reasons, but no use is made of supplied options.

- **-S** *saltfile*

  When **-K** is used, specify the *saltfile*.

- **-t** *disktype*

  Specify a *disktype* entry from the [disktab(5)](/disktab/5.md) database. The *vnd\_dev* will have the sector size, sectors per track, and tracks per cylinder values of the specified *disktype*. The defaults are 512-byte sectors, 100 sectors per track and 1 track per cylinder.

## FILES

- */dev/{,r}vnd\**

  ## EXAMPLES

An example [fstab(5)](/fstab/5.md) entry is:

```
/tmp/cryptimg /dev/vnd0c vnd rw,noauto,-k       0 0
/dev/vnd0a   /mnt        ffs rw,noauto          0 0
```

Mounting images during the first pass of [fsck(8)](/fsck/8.md) and [mount(8)](/mount/8.md) is not possible, because the image to be configured to a vnd itself resides on a file system that first has to be checked and mounted.

## SEE ALSO

[vnd(4)](/vnd/4.md), [disktab(5)](/disktab/5.md), [fstab(5)](/fstab/5.md), [mount(8)](/mount/8.md), [swapon(8)](/swapon/8.md), [umount(8)](/umount/8.md)

## HISTORY

The **mount\_vnd** command first appeared in OpenBSD 4.2.