qq2clone/man.pandoc

% QQ2CLONE(1) qq2clone
% Jesse Gardner
% February 2021

# NAME
qq2clone - Create and manage QEMU/KVM VMs using template machines and qcow2
  images with backing files
  
# SYNOPSIS
**qq2clone** [*OPTION*]... *COMMAND* [*ARG*]...

# DESCRIPTION
**qq2clone** is a tool for creating and managing clones of QEMU/KVM 
virtual machines. By using the copy on write feature of qcow2, clones of 
an existing virtual machine can be made using few system resources and 
little time or effort.

**qq2clone** supports creating numerous clones of a template and 
performing batch operations on them - including the execution of arbitrary 
commands with **qq2clone** exec. This simplifies workflows involving large 
numbers of virtual machines, or the frequent creation/deletion of virtual 
machines.

To easily establish graphical connections to your virtual machines, qq2clone
can use virt-viewer or spicy.
 
# OPTIONS

Not every option has an effect in the context of every command. Specifying 
an option that has no effect in the context of the command being invoked 
will not produce an error, it simply will not do anything.

Options are parsed left to right, and right-hand options override 
left-hand options.

\-c, \-\-connection  [*URI*] 
: Specify a non-default connection URI: sets the value of 
LIBVIRT_DEFAULT_URI

\-C, \-\-copy\-disks
: When importing or copying a template, make a (full) copy of its image(s)

\-f, \-\-no\-spice
: Do not attempt to connect to a virtual machine's Spice graphics. 
Overrides USE_SPICE setting in configuration

\-g, \-\-use\-spice
: Attempt to connect to a virtual machine's spice graphics. Overrides 
SPICE setting in configuration

\-h, \-\-help
: Print basic help information and exit

\-n, \-\-no-run
: After making a clone of a template, do not run it. Overrides NORUN 
setting in configuration

\-q, \-\-quiet
: Suppress most non-error output. Overrides QUIET setting in 
configuration. Also suppresses various prompts for user choices, either 
exiting with an error or making a safe default choice depending on the 
command. Recommended only once familiar with the behavior of **qq2clone**

\-Q, \-\-quieter
: This option is (currently) required to appear as the first 
argument to **qq2clone**. Suppresses all output, error message or 
otherwise, except when running interactive commands or 
commands that require output to be useful. Other 
commands will receive only an exit code as output. This option is intended
for calling qq2clone from a script.

\-r, \-\-run
: Start a clone after creating it. Overrides NORUN setting in configuration

\-s, \-\-storage [*LOCATION*]
: When creating a clone, place new disk image file(s) at location 
specified by [*LOCATION*]. [*LOCATION*] may be one of an absolute 
filepath, or the name of a libvirt directory type storage pool. Also 
defines where state files will be saved when using **save** command. 
Overrides STORAGE option in configuration

\-S, \-\-spicy
: Use spicy rather than virt-viewer when connecting to the spice graphics 
of a clone. Overrides SPICY setting in configuration

\-t, \-\-template [*NAME*]
: Use template of given name as context when executing a clone command 
(see TYPES OF COMMAND section below). Overrides TEMPLATE option in 
configuration

\-v, \-\-verbose
: Enable all output. Overrides QUIET setting in configuration

\-V, \-\-virt\-viewer
: Use virt-viewer rather than spicy when connecting to the spice graphics 
of a clone. Overrides SPICY setting in configuration

# TYPES OF COMMAND

There are two main classes of commands: commands that operate directly on 
templates, and commands that create or operate on clones of templates. To 
prevent unintended actions, these two command types use slightly 
different syntax. Commands that operate on templates use the syntax: 


**qq2clone** **command** [*template-name*] [*ARG*] ... 

while commands that operate on clones use the syntax: 

**qq2clone** \-\-template [*template-name*] **command** [*ARG*] ... 

Commands operating on clones work within the context of a 
template defined by \-\-template/\-t. Conversely, commands 
operating on templates specify the template as an  argument to the 
command. 

A default template can be defined by the 
TEMPLATE configuration option, allowing the \-\-template 
flag to be omitted for commands that operate on clones. Commands 
operating on templates do not respect this default - the template must 
always be explicitly defined, reducing the likelihood of 
accidentally modifying or deleting a template.

# TEMPLATE COMMMANDS

**copy-template** [*CURRENT-NAME*] [*NEW-NAME*]
: Copy the XML of template *CURRENT-NAME* to a new template with 
*NEW-NAME*. The new template will not receive a copy of the old template's
storage devices - it will point to the same locations

**delete-template** [*NAME*]
: Delete the template *NAME*. This operation will succeed only if there 
are currently no clones of the template

**import-template** [*LIBVIRT-DOMAIN*] [*NAME*], **import-template** 
[*XML-LOCATION*] [*NAME*]
: Import a new template from either an existing libvirt domain, or a fully 
qualified filepath to a libvirt domain XML file on disk. If argument 
*NAME* is ommited, qq2clone will assume you want to use the machine's name 
as described in the XML file as the template name

**list-templates**
: List the names of all existing templates

**modify-template** [*NAME*] **sub-command** [*ARG*] ...
: Templates can be modified in various ways by invoking 
**modify-template**. Each subcommand is described below

**modify-template** [*NAME*] **commit-image**
: After an image has been created and modified as desired using 
**modify-template**  [*NAME*] **prepare-image**, **commit-image** is used 
to alter a template's underlying storage device by commiting any changes 
made using prepare-image. See the commit command described in **man** 
**qemu-img** for more information on how this works

**modify-template** [*NAME*] **destroy-image**
: Invoke virsh destroy on a running image created/run through 
**modify-template** [*NAME*] **prepare-image**. This is generally not 
wise, as it is equivalent to unplugging a physical machine and could cause 
corruption to the image that will later be commited as a permanent change 
to the template's image

**modify-template** [*NAME*] **discard-image**
: Delete an image produced by **modify-template** [*NAME*] 
**prepare-image** without commiting any changes

**modify-template** [*NAME*] **edit**
: Edit the XML document defining a template

**modify-template** [*NAME*] **rename** [*NEW-NAME*]
: Change the name of a template, and all of its clones

**modify-template** [*NAME*] **prepare-image**
: Create and/or run a clone  that acts as a staging area for changes to 
the `template's` actual image. For instance, you could update the 
`template's` software by running **modify-template** [*NAME*] 
**prepare-image**, updating the clone produced by this command,
shutting it down, and then running **modify-template** [*NAME*] 
**commit-image**. This serves a twofold purpose - to prevent incidental 
damage to an underlying image by providing a safe buffer to work in, and 
to allow modifications to be safely prepared for an underlying image even 
while that image has existing clones.

# CLONE COMMANDS

A description of the argument *SET* is described in the **SETS** section 
below

**clone** [*NUMBER*]
: Invoke without any argument to produce a single clone. Supply a number 
as an argument to specify the number of clones to create

**connect** [*SET*]
: Start any machine in *SET* that `isn't` already running. If any machine 
in *SET* has spice graphics and spicy or virt-viewer is installed, use one 
or the other (chosen by command-line option or configuration) to connect 
to the graphical console

**destroy** [*SET*]
: Invoke virsh destroy on any running machine in *SET* (in other words, if 
the domain is running forcibly turn it off)

**edit** [*NUMBER*]
: Edit the XML file of the clone with given number

**exec** [*SET*] [*command-string*]
: For every machine in *SET*, sequentially, execute the contents of the 
command string in an environment where the following variables are defined 
per clone: `"$uuid"`, `"$name"`, `"$disks"` (a newline delimited string 
containing the machine's qcow2 disk device filepaths). This is done using 
bash's eval command, so contain the command string in single quotes to 
avoid unexpected behavior. If any instance of exec has a non-zero 
return value, execution stops.

**list** [*ARG*]
: Without arguments, list all clones of the current template and their 
state. With argument "all", provide list including all clones of every 
template. With argument "xml", produce an XML document with information 
about every template, their clones, and their state. The XML option 
is not complete - its format is at this point defined only implicitly, by 
the output of this command.

**resume** [*SET*]
: Resume any suspended machines in *SET*

**rm** [*SET*]
: Destroy every domain in *SET* (if running), undefine them and delete 
their storage volumes

**rm-wipe** [*SET*]
: Destroy every domain in *SET* (if running), undefine them and wipe their 
storage volumes using virsh

**rm-shred** [*SET*]
: Destroy every domain in *SET* (if running), undefine them and shred 
their storage volumes

**save** [*SET*]
: Save execution state of every running domain in *SET* to file

**save-rm** [*SET*]
: Delete the state file associated with every machine in *SET*

**start** [*SET*]
: Start every machine in *SET* that is currently not running. For saved 
domains, their state will be restored

**suspend** [*SET*]
: Suspend execution of every machine in *SET*

# OTHER COMMANDS

**check** [*TEMPLATE-NAME*]
: If a clone is deleted, has its UUID changed or is otherwise unavailable, 
it will remain in qq2clone's database. Its ID number will remain 
reserved, and its image files may not be deleted and take up space doing 
nothing. The **check** command finds and fixes occurences of this problem. 
The *TEMPLATE-NAME* argument is optional, and restricts the check to that 
template and its clones. Otherwise, all templates are checked

**config** list, **config** info [*OPTION*], **config** edit [*OPTION*]
: List all configuration options and their current value, get info about a 
particular option, or edit one

**copyright**
: Output copyright information

**license**
: Output the GNU GPL v2 complete text

**setup**
: Perform initial setup. This is run automatically by the installer script,
but can be invoked manually to reset the database to its initial fresh state

# SETS	

*SET* is listed as an argument to many commands. *SET* simply describes a 
set of virtual machines - clones of a given template. *SET* is a comma 
delimited list with no whitespace. *SET* can be an individual machine or 
several individual machines designated by number:

    1                 (Machine 1)
    3,7               (Machines 3 and 7)

Machine numbers can be shown with **qq2clone** **list**. Ranges and 
omitted values are supported as well:

    1,2-5,^3          (Machines 1 and 2-5 excluding 3)
    1-10,^3-7         (Machines 1-10 excluding 3-7)

Lastly, groups of machines can be addressed by their state:

    all               (All machines)
    all,^running      (All machines that aren't running)
    ^running,1-10     (Machines 1-10 except those that are running)

The possible states of a virtual machine are based on the states listed in 
**man virsh**, with some modifications. States in qq2clone are: 

    all
    crashed
    idle
    in-shutdown
    off
    paused
    pmsuspended
    running
    saved

Specifying machines that do not exist will not cause an error: i.e., 
1-10 is a valid set even if only machines 3-7 exist. A set will only cause 
an error if it is malformed, includes zero existing machines, contains no 
machines that the command being invoked may act upon, or includes numbers 
less than 1.

# CONFIG

There is no need to refer to the manual to understand configuration 
options. Use "**qq2clone** config list" to see all options and their 
current values, and "**qq2clone** config info [*OPTION*]" to get 
information about a particular option. However, here is the same 
information provided by **qq2clone** info for each option

TEMPLATE

> This template will be used for commands like clone, rm, destroy when 
option \-\-template/\-t is not specified
>
> Default value: `'0'`

TEMPLATE_DIR

> This is the where template XML files will be kept
>
> Default value: `'${HOME}/storage-qq2clone/templates'`

QUIET

> If set to 1, most non-error output will be suppressed
>
> Default value: `'0'`

USE_SPICE

> If set to 1, attempt to connect 
> to the spice graphics of a virtual machine by default when cloning it, 
if it is configured to use spice graphics. qq2clone can do this using the 
programs spicy and virt-viewer. If either is installed on your system 
during the first run, the default value is `'1'` (enabled). Otherwise, the 
default value is `'0'`

S_TIMEOUT

> Wait this many seconds before timing out when trying to connect to a 
virtual `machine's` spice graphics.
>
> Default value: `'10'`

STORAGE

> The default location to store clone images when creating them. Changing 
this location is fine, but it is a good idea to ensure that whatever 
location you do choose is only used by qq2clone
>
> Default value: `'${HOME}/storage-qq2clone/qq2clone-pool'`

# EXAMPLES

**qq2clone** **import-template** Debian
: Import a domain on the current libvirt connection of name Debian. Now Debian can
be used as a template to produce clone machines

**qq2clone** **import-template** /home/user/Debian.xml
: Import domain from a libvirt domain XML file to be used as a template

**qq2clone** \-\-template Debian \-\-run \-\-virt-viewer clone
: Make a clone of Debian, run it, and connect to its spice graphics using 
virt\-viewer. All of these options could have instead been defined in the 
configuration, so that the entire command would be: **qq2clone** clone

**qq2clone** \-\-template Debian exec 3 'virsh console "$uuid"'
: Use virsh to connect to the serial console of template Debian's clone 
with number 3 (as shown in **qq2clone** list)

**qq2clone** **modify-template** Debian **prepare-image**
: Create a clone of Debian that can be used as a staging area for 
permanent changes to the backing template storage device

**qq2clone** **modify-template** Debian **commit-image**
: Commit changes to the image Debian staged with the previous command

**qq2clone** **copy-template** Debian Debian_2
: Copy the XML of template Debian, creating a new template with the same 
backing storage device that you can edit as you please

# LIMITATIONS

Understand what copy on write is. If you modify an image, you will
corrupt images using it as a backing file. If you don't understand what 
that means, use a search engine to research copy on write. To safely modify 
a template's underlying image, use the prepare-image and commit-image 
subcommands of **qq2clone** modify-template.

qq2clone uses a virtual machine's UUID as defined in its libvirt XML 
file to track it. Don't change a clone's UUID.

qq2clone does not support pool types other than directories. If there is 
another pool type you wish it could use, email me at 
jgardner7289@protonmail.com and let me know.

# FILES

~/.config/qq2clone

: This document simply contains a string defining the location at which
qq2clone will store files, including the database containing the rest of
it configuration options. Currently, qq2clone cannot run without ${HOME}
being defined unless a few lines are altered to refer to a new location

~/storage-qq2clone

: Directory where qq2clone stores all files and binary executables. Can be 
changed by modifying ~/.config/qq2clone. This directory is not 
named "qq2clone" because (at least on Ubuntu 20.04) default  Bash completion
scripts will see a file starting with "qq2clone" as well as a command in
PATH of that name, and fail to insert a space after "qq2clone"
when in the home directory. It does not start with a '.' 
for the reasons described in the **LIMITATIONS** section above

~/storage-qq2clone/qq2clone.db
: sqlite3 database containing the configuration information for qq2clone, 
as well as data about templates and clones

~/storage-qq2clone/qq2clone-pool

: Storage pool used for clone images, if the 
\-\-storage option is not used when creating or saving a clone and the 
option STORAGE is not changed in the configuration file

~/qq2clone/templates

: Directory in which template XML files are stored. These can be edited 
manually, but it is more advisable to use **qq2clone** **modify-template** 
[*template-name*] **edit**

# BUGS

If you find a bug, please check to see if it already appears in 
https://git.j-g-web.com/jesse/qq2clone/issues. If not, email me at
jgardner7289@protonmail.com.

# COPYRIGHT 2021, Jesse Gardner

This file is part of qq2clone.

qq2clone 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.

qq2clone 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 qq2clone.  If not, see <https://www.gnu.org/licenses/>.

# EXIT VALUES

**10**	
: No permission to access file or file doesn't exist

**11**
: Required software dependencies are not met (see description for a list), 
or are cannot be found in PATH

**12**
: Invalid command line argument specified, or command specifies an invalid 
action

**13**
: Problem with a template - i.e., specified template does not exist, or 
import-template failed because template of specified name already exists

**14**
: Invocation of an external command failed

**15**
: Problem with a libvirt XML file

**16**
: Attempted action with a libvirt tool resulted in failure

**17**
: Could not establish graphical spice connection to machine before timeout 
expired

**18**
: A file is of the wrong type or does not exist

**19**
: Unexpected error - a bug in qq2clone, or a highly unexpected failure of 
some command