1.\"- 2.\" Copyright (c) 2010 Edward Tomasz Napierala 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.Dd September 28, 2026 26.Dt GMOUNTVER 8 27.Os 28.Sh NAME 29.Nm gmountver 30.Nd "control utility for disk mount verification GEOM class" 31.Sh SYNOPSIS 32.Nm 33.Cm create 34.Op Fl v 35.Ar prov ... 36.Nm 37.Cm destroy 38.Op Fl fv 39.Ar name 40.Nm 41.Op Fl -libxo 42.Cm list 43.Nm 44.Op Fl -libxo 45.Cm status 46.Op Fl s Ar name 47.Nm 48.Cm load 49.Op Fl v 50.Nm 51.Cm unload 52.Op Fl v 53.Sh DESCRIPTION 54The 55.Nm 56utility is used to control the mount verification GEOM class. 57When configured, it passes all the I/O requests to the underlying provider. 58When the underlying provider disappears - for example because the disk device 59got disconnected - it queues all the I/O requests and waits for the provider 60to reappear. 61When that happens, it attaches to it and sends the queued requests. 62.Pp 63The first argument to 64.Nm 65indicates an action to be performed: 66.Bl -tag -width ".Cm destroy" 67.It Cm create 68Enable mount verification for the given provider. 69If the operation succeeds, a new GEOM provider will be created using the 70given provider's name with a 71.Ql .mountver 72suffix. 73The kernel module 74.Pa geom_mountver.ko 75will be loaded if it is not loaded already. 76.It Cm destroy 77Destroy 78.Ar name . 79.It Cm list 80See 81.Xr geom 8 . 82.It Cm status 83See 84.Xr geom 8 . 85.It Cm load 86See 87.Xr geom 8 . 88.It Cm unload 89See 90.Xr geom 8 . 91.It Fl -libxo 92Generate output via 93.Xr libxo 3 94in a selection of different human and machine readable formats. 95See 96.Xr xo_options 7 97for details on command line arguments. 98.El 99.Pp 100Additional options: 101.Bl -tag -width indent 102.It Fl f 103Force the removal of the specified mountver device. 104.It Fl v 105Be more verbose. 106.El 107.Sh SYSCTL VARIABLES 108The following 109.Xr sysctl 8 110variables can be used to control the behavior of the 111.Nm MOUNTVER 112GEOM class. 113The default value is shown next to each variable. 114.Bl -tag -width indent 115.It Va kern.geom.mountver.debug : No 0 116Debug level of the 117.Nm MOUNTVER 118GEOM class. 119This can be set to a number between 0 and 3 inclusive. 120If set to 0 minimal debug information is printed, and if set to 3 the 121maximum amount of debug information is printed. 122.It Va kern.geom.mountver.check_ident : No 1 123This can be set to 0 or 1. 124If set to 0, 125.Nm 126will reattach to the device even if the device reports a different disk ID. 127.El 128.Sh EXIT STATUS 129Exit status is 0 on success, and 1 if the command fails. 130.Sh SEE ALSO 131.Xr geom 4 , 132.Xr xo_options 7 , 133.Xr geom 8 134.Sh HISTORY 135The 136.Nm 137utility appeared in 138.Fx 9.0 . 139.Sh AUTHORS 140.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org 141