path: root/sys-utils/switch_root.8

.\" Karel Zak <kzak@redhat.com>
.TH SWITCH_ROOT 8 "June 2009" "util-linux" "System Administration"
.SH NAME
switch_root \- switch to another filesystem as the root of the mount tree
.SH SYNOPSIS
.B switch_root
.RB [ \-hV ]
.LP
.B switch_root
.I newroot
.I init
.RI [ arg ...]
.SH DESCRIPTION
.B switch_root
moves already mounted /proc, /dev, /sys and /run to
.I newroot
and makes
.I newroot
the new root filesystem and starts
.I init
process.

.B WARNING: switch_root removes recursively all files and directories on the current root filesystem.

.SH OPTIONS
.IP "\fB\-h, \-\-help\fP"
Display help text and exit.
.IP "\fB\-V, \-\-version\fP"
Display version information and exit.

.SH RETURN VALUE
.B switch_root
returns 0 on success and 1 on failure.

.SH NOTES
switch_root will fail to function if
.B newroot
is not the root of a mount. If you want to switch root into a directory that
does not meet this requirement then you can first use a bind-mounting trick to
turn any directory into a mount point:
.sp
.nf
.RS
mount --bind $DIR $DIR
.RE
.fi

.SH "SEE ALSO"
.BR chroot (2),
.BR init (8),
.BR mkinitrd (8),
.BR mount (8)
.SH AUTHORS
.nf
Peter Jones <pjones@redhat.com>
Jeremy Katz <katzj@redhat.com>
Karel Zak <kzak@redhat.com>
.fi
.SH AVAILABILITY
The switch_root command is part of the util-linux package and is available from
https://www.kernel.org/pub/linux/utils/util-linux/.