class/mountver/gmountver.8

    gmountver.8 revision 307403
    -
 Copyright (c) 2010 Edward Tomasz Napierala
 All rights reserved.

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 $FreeBSD: stable/10/sbin/geom/class/mountver/gmountver.8 307403 2016-10-16 22:02:50Z sevan $

.Dd January 27, 2015
.Dt GMOUNTVER 8
.Os
.Sh NAME
.Nm gmountver
.Nd "control utility for disk mount verification GEOM class"
.Sh SYNOPSIS
.Nm
.Cm create
.Op Fl v
.Ar dev ...
.Nm
.Cm destroy
.Op Fl fv
.Ar prov ...
.Nm
.Cm list
.Nm
.Cm status
.Op Fl s Ar name
.Nm
.Cm load
.Op Fl v
.Nm
.Cm unload
.Op Fl v
.Sh DESCRIPTION
The
.Nm
utility is used to control the mount verification GEOM class.
When configured, it passes all the I/O requests to the underlying provider.
When the underlying provider disappears - for example because the disk device
got disconnected - it queues all the I/O requests and waits for the provider
to reappear.
When that happens, it attaches to it and sends the queued requests.
p
The first argument to
.Nm
indicates an action to be performed:
l -tag -width ".Cm destroy" t Cm create Cache the given devices with specified
.Ar name .
The kernel module
a geom_mountver.ko
will be loaded if it is not loaded already.
t Cm destroy Destroy
.Ar name .
t Cm list See
.Xr geom 8 .
t Cm status See
.Xr geom 8 .
t Cm load See
.Xr geom 8 .
t Cm unload See
.Xr geom 8 .
.El
p
Additional options:
l -tag -width indent t Fl f Force the removal of the specified mountver device.
t Fl v Be more verbose.
.El
.Sh SYSCTL VARIABLES
The following
.Xr sysctl 8
variables can be used to control the behavior of the
.Nm MOUNTVER
GEOM class.
The default value is shown next to each variable.
l -tag -width indent t Va kern.geom.mountver.debug : No 0 Debug level of the
.Nm MOUNTVER
GEOM class.
This can be set to a number between 0 and 3 inclusive.
If set to 0 minimal debug information is printed, and if set to 3 the
maximum amount of debug information is printed.
t Va kern.geom.mountver.check_ident : No 1 This can be set to 0 or 1.
If set to 0,
.Nm
will reattach to the device even if the device reports a different disk ID.
.El
.Sh EXIT STATUS
Exit status is 0 on success, and 1 if the command fails.
.Sh SEE ALSO
.Xr geom 4 ,
.Xr geom 8
.Sh HISTORY
The
.Nm
utility appeared in
.Fx 9.0 .
.Sh AUTHORS
.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org