xref: /freebsd/sbin/mksnap_ffs/mksnap_ffs.8 (revision c8cf3f3d0e48740c32c2b7ea85f7098298b34a52)

.\"
.\" Copyright (c) 2003 Networks Associates Technology, Inc.
.\" All rights reserved.
.\"
.\" This software was developed for the FreeBSD Project by Marshall
.\" Kirk McKusick and Network Associates Laboratories, the Security
.\" Research Division of Network Associates, Inc. under DARPA/SPAWAR
.\" contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
.\" research program.
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.\" $FreeBSD$
.\"
.Dd May 29, 2009
.Dt MKSNAP_FFS 8
.Os
.Sh NAME
.Nm mksnap_ffs
.Nd take a file system snapshot
.Sh SYNOPSIS
.Nm
.Ar snapshot_name
.Sh DESCRIPTION
The
.Nm
utility creates a snapshot named
.Ar snapshot_name .
.Pp
The group ownership of the file is set to
.Dq Li operator ;
the owner of the file remains
.Dq Li root .
The mode of the snapshot is set to be readable by the owner
or members of the
.Dq Li operator
group.
.Sh EXAMPLES
Create a snapshot of
.Pa /usr/home
file system and mount the snapshot elsewhere:
.Bd -literal -offset indent
mksnap_ffs /usr/home/snapshot
mdconfig -a -t vnode -o readonly -f /usr/home/snapshot
mount -o ro /dev/md0 /mnt/
.Ed
.Sh SEE ALSO
.Xr chmod 2 ,
.Xr chown 8 ,
.Xr mdconfig 8,
.Xr mount 8
.Sh CAVEATS
The disk full situation is not handled gracefully and may
lead to a system panic when no free blocks are found.
.Sh HISTORY
The
.Nm
utility first appeared in
.Fx 5.0 .