VN(4)

NAME
vn - vnode disk driver

SYNOPSIS
pseudo-device vn [n]

Alternatively, to load the driver as a module at boot time, place the following line in /boot/loader.conf:

    vn_load="YES"

DESCRIPTION
The vn driver uses swap or a file as backing store to abstract-out a device which may then be used like a disk. The vn driver supports both labeled and unlabeled pseudo-disks and is useful for a variety of applications, including swap files and building mini-root, floppy, or CD-ROM disk images. vn may also be used to create temporary swap-backed filesystems, such as /tmp, in a somewhat less memory-hungry manner than MFS.

The vn driver supports autocloning. By default 4 vn devices are also precreated.

FILES
/dev/vn*
    vn device special files

SEE ALSO
fsck(8), mount(8), mount_mfs(8), newfs(8), vnconfig(8)

HISTORY
The vnode disk driver was originally written at the University of Utah and was substantially modified by FreeBSD developers to add swap-backed support.

BUGS
The vn driver does not work if the file does not reside in a local filesystem.