virt-format(1)
NAME
virt-format - Erase and make a blank disk
SYNOPSIS
virt-format [--options] -a disk.img [-a disk.img ...]
WARNING
Using "virt-format" on live virtual machines, or concurrently with other disk editing tools, can be dangerous, potentially causing disk corruption. The virtual machine must be shut down before you use this command, and disk images must not be edited concurrently.
DESCRIPTION
Virt-format takes an existing disk file (or it can be a host partition, LV etc), erases all data on it, and formats it as a blank disk. It can optionally create partition tables, empty filesystems, logical volumes and more. To create a disk containing data, you may be better to use virt-make-fs(1). If you are creating a blank disk to use in guestfish(1), you should instead use the guestfish -N option. Normal usage would be something like this: virt-format -a disk.qcow or this: virt-format -a /dev/VG/LV disk.qcow or /dev/VG/LV must exist already. Any data on these disks will be erased by these commands. These commands will create a single empty partition covering the whole disk, with no filesystem inside it. Additional parameters can be used to control the creation of partitions, filesystems, etc. The most commonly used options are: --filesystem=[ext3|ntfs|vfat|...] Create an empty filesystem ("ext3", "ntfs" etc) inside the partition. --lvm[=/dev/VG/LV] Create a Linux LVM2 logical volume on the disk. When used with --filesystem, the filesystem is created inside the LV. For more information about these and other options, see "OPTIONS" below. The format of the disk is normally auto-detected, but you can also force it by using the --format option (q.v.). In situations where you do not trust the existing content of the disk, then it is advisable to use this option to avoid possible exploits.
OPTIONS
--help
Display brief help.
-a file
--add file
Add file, a disk image, host partition, LV, external USB disk, etc.
The format of the disk image is auto-detected. To override this
and force a particular format use the --format=.. option.
Any existing data on the disk is erased.
-a URI
--add URI
Add a remote disk. See "ADDING REMOTE STORAGE" in guestfish(1).
--filesystem=ext3|ntfs|vfat|...
Create an empty filesystem of the specified type. Many filesystem
types are supported by libguestfs.
--filesystem=none
Create no filesystem. This is the default.
--format=raw|qcow2|..
--format
The default for the -a option is to auto-detect the format of the
disk image. Using this forces the disk format for -a options which
follow on the command line. Using --format with no argument
switches back to auto-detection for subsequent -a options.
For example:
virt-format --format=raw -a disk.img
forces raw format (no auto-detection) for disk.img.
virt-format --format=raw -a disk.img --format -a another.img
forces raw format (no auto-detection) for disk.img and reverts to
auto-detection for another.img.
If you have untrusted raw-format guest disk images, you should use
this option to specify the disk format. This avoids a possible
security problem with malicious guests (CVE-2010-3851).
--label=LABEL
Set the filesystem label.
--lvm=/dev/VG/LV
Create a Linux LVM2 logical volume called /dev/VG/LV. You can
change the name of the volume group and logical volume.
--lvm
Create a Linux LVM2 logical volume with the default name
(/dev/VG/LV).
--lvm=none
Create no logical volume. This is the default.
--partition
Create either an MBR or GPT partition covering the whole disk. MBR
is chosen if the disk size is < 2 TB, GPT if 2 TB.
This is the default.
--partition=gpt
Create a GPT partition.
--partition=mbr
Create an MBR partition.
--partition=none
Create no partition table. Note that Windows may not be able to
see these disks.
-v
--verbose
Enable verbose messages for debugging.
-V
--version
Display version number and exit.
--wipe
Normally virt-format does not wipe data from the disk (because that
takes a long time). Thus if there is data on the disk, it is only
hidden and partially overwritten by virt-format, and it might be
recovered by disk editing tools.
If you use this option, virt-format writes zeroes over the whole
disk so that previous data is not recoverable.
-x Enable tracing of libguestfs API calls.
EXIT STATUS
This program returns 0 on success, or 1 on failure.
SEE ALSO
guestfs(3), guestfish(1), virt-filesystems(1), virt-make-fs(1), virt-rescue(1), virt-resize(1), http://libguestfs.org/.
AUTHOR
Richard W.M. Jones http://people.redhat.com/~rjones/
COPYRIGHT
Copyright (C) 2012 Red Hat Inc.
LICENSE
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
BUGS
To get a list of bugs against libguestfs, use this link:
https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
To report a new bug against libguestfs, use this link:
https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
When reporting a bug, please supply:
* The version of libguestfs.
* Where you got libguestfs (eg. which Linux distro, compiled from
source, etc)
* Describe the bug accurately and give a way to reproduce it.
* Run libguestfs-test-tool(1) and paste the complete, unedited output
into the bug report.
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
