^^^^^
snf-image-creator comes in 2 variants:
+
* snf-image-creator: A non-interactive command line program
* snf-mkimage: A user-friendly dialog-based program
+Both expect the input media as first argument. The input media may be a local
+file, a block device or *"/"* if you want to create an image out of the running
+system (see `host bundling operation`_).
+
Non-interactive version
=======================
.. code-block:: console
$ snf-image-creator --help
-
Usage: snf-image-creator [options] <input_media>
Options:
- --version show program's version number and exit
- -h, --help show this help message and exit
- -o FILE, --outfile=FILE
- dump image to FILE
- -f, --force overwrite output files if they exist
- -s, --silent silent mode, only output errors
- -u FILENAME, --upload=FILENAME
- upload the image to pithos with name FILENAME
- -r IMAGENAME, --register=IMAGENAME
- register the image with ~okeanos as IMAGENAME
- -a ACCOUNT, --account=ACCOUNT
- Use this ACCOUNT when uploading/registering images
- [Default: None]
- -m KEY=VALUE, --metadata=KEY=VALUE
- Add custom KEY=VALUE metadata to the image
- -t TOKEN, --token=TOKEN
- Use this token when uploading/registering images
- [Default: None]
- --print-sysprep print the enabled and disabled system preparation
- operations for this input media
- --enable-sysprep=SYSPREP
- run SYSPREP operation on the input media
- --disable-sysprep=SYSPREP
- prevent SYSPREP operation from running on the input
- media
- --no-sysprep don't perform system preparation
- --no-shrink don't shrink any partition
-
-
-Most input options are self-describing. If you want to save a local copy for
-the image you create, you specify *-o* option. To upload the image to
-*pithos+*, you specify valid credentials with *-a* and *-t* options and a
-filename using *-u*. If you want to register the image with *~okeanos*,
-in addition to *-u* specify a registration name using *-r*.
-
-By default snf-image-creator will perform a number of system preparation
-operations on the snapshot of the media and will shrink the last partition
-found, before extracting the image. Both can be disabled by specifying
+ --version show program's version number and exit
+ -h, --help show this help message and exit
+ -o FILE, --outfile=FILE
+ dump image to FILE
+ -f, --force overwrite output files if they exist
+ -s, --silent output only errors
+ -u FILENAME, --upload=FILENAME
+ upload the image to pithos with name FILENAME
+ -r IMAGENAME, --register=IMAGENAME
+ register the image with ~okeanos as IMAGENAME
+ -m KEY=VALUE, --metadata=KEY=VALUE
+ add custom KEY=VALUE metadata to the image
+ -t TOKEN, --token=TOKEN
+ use this token when uploading/registering images
+ [Default: None]
+ --print-sysprep print the available enabled and disabled system
+ preparation operations for this input media
+ --enable-sysprep=SYSPREP
+ run SYSPREP operation on the input media
+ --disable-sysprep=SYSPREP
+ prevent SYSPREP operation from running on the input
+ media
+ --no-sysprep don't perform any system preparation operation
+ --no-shrink don't shrink the image
+ --public register image with cyclades as public
+ --tmpdir=DIR create large temporary image files under DIR
+
+Most input options are self-describing. If you want to save a local copy of
+the image you create, provide a filename using the *-o* option. To upload the
+image to *pithos+*, provide a valid authentication token using *-t* and a
+filename using *-u*. If you also want to register the image with *~okeanos*, in
+addition to *-u* provide a registration name using *-r*. All images are
+registered as *private*. Only the user that registers the image can create
+VM's out of it. If you want the image to be visible by other user too, use the
+*--public* option.
+
+By default, before extracting the image, snf-image-creator will perform a
+number of system preparation operations on the snapshot of the media and will
+shrink the last partition found. Both actions can be disabled by specifying
*--no-sysprep* and *--no-shrink* respectively.
-If *--print-sysprep* is defined, the program will exit after outputing a
-list of enabled and disabled system preparation operation appliable to this
-media source. The user can enable or disable specific *syspreps* when creating
-an image, using *-{enable,disable}-sysprep* options. You can specify those
-options multiple times to enable or disable multiple *syspreps*.
+If *--print-sysprep* is defined, the program will exit after printing a
+list of enabled and disabled system preparation operation applicable to this
+input media. The user can enable or disable specific *syspreps*, using
+*-{enable,disable}-sysprep* options. The user may specify those options
+multiple times.
Running *snf-image-creator* with *--print-sysprep* on a raw file that hosts a
-debian system, we get the following output:
+debian system, we print the following output:
.. _sysprep:
cleaning up...
-If we want the image to have all normal user accounts and all mail files
-removed, we can create it specifying *--enable-sysprep* option like this:
+If you want the image to have all normal user accounts and all mail files
+removed, you should use *--enable-sysprep* option like this:
.. code-block:: console
.. code-block:: console
- $ Usage: snf-mkimage [options] [<input_media>]
+ $ snf-mkimage --help
+ Usage: snf-mkimage [options] [<input_media>]
- Options:
- --version show program's version number and exit
- -h, --help show this help message and exit
- -l FILE, --logfile=FILE
- log all messages to FILE
+ Options:
+ --version show program's version number and exit
+ -h, --help show this help message and exit
+ -l FILE, --logfile=FILE
+ log all messages to FILE
+ --tmpdir=DIR create large temporary image files under DIR
If the input media is not specified in the command line, in the first dialog
-box the user will be asked to specify it. After the input media is examined and
-the program is initialized, the user will be given the choice to run
-*snf-mkimage* in *wizard* or *expert* mode.
+box the user will be asked to specify it:
+
+.. image:: /snapshots/select_media.png
+
+The user can select a file (regular or block device) or use the *Bundle Host*
+button to create an image out of the running system (see
+`Host bundling operation`_).
+
+After the input media is examined and the program is initialized, the user will
+be given the choice to run *snf-mkimage* in *wizard* or *expert* mode.
Wizard mode
-----------
following basic information:
* Name: A short name for the image (ex. "Slackware")
- * Description: An one-line description for the image (ex. "Slackware Linux 14.0 with KDE")
- * Account: An *~okeanos* account email
- * Token: A token corresponding to the account defined previously
+ * Description: An one-line description for the image
+ (ex. "Slackware Linux 14.0 with KDE")
+ * Registration Type: Private or Public
+ * Account: The authentication token for an *~okeanos* account
After confirming, the image will be extracted, uploaded to *pithos+* and
-registered to *~okeanos*. The user will also be given the choice to keep a local
-copy of it. For most users the functionality this mode provides should be
-sufficient.
+registered with *~okeanos*. The user will also be given the choice to keep a
+local copy of it.
+
+For most users the functionality this mode provides should be sufficient.
Expert mode
-----------
Expert mode allows the user to have better control on the image creation
-process. In the picture below the main menu can be seen:
+process. The main menu can be seen in the picture below:
.. image:: /snapshots/main_menu.png
In the *Register* sub-menu the user can provide:
- * The credentials to login to *~okeanos*
- * A pithos filename for the uploaded *diskdump* image
- * A name for the image to be registered to *~okeanos* with
+ * The credentials (authentication token) to use when authenticating
+ to *~okeanos*
+ * A *pithos+* filename for the uploaded *diskdump* image
+ * A name for the image to use when registering it with *~okeanos*, as well as
+ the registration type (*private* or *public*)
-By choosing the *Extract* menu entry the user can dump the image to the local
-file system and finally, if the user selects *Reset*, the system will ignore
+By choosing the *Extract* menu entry, the user can dump the image to the local
+file system. Finally, if the user selects *Reset*, the system will ignore
all changes made so far and will start the image creation process again.
+Host bundling operation
+=======================
+
+As a new feature in *v0.2*, snf-image-creator can create images out of the host
+system that runs the program. This is done either by specifying / as input
+media or by using the *Bundle Host* button in the media selection dialog of
+snf-mkimage. During this operation, the files of the disk are copied into a
+temporary image file, which means that the file system that will host the
+temporary image needs to have a lot of free space (see `large temporary files`_
+for more information).
+
Creating a new image
====================
.. code-block:: console
- $ wget http://ubuntureleases.tsl.gr/12.04.1/ubuntu-12.04.1-server-amd64.iso
+ $ wget http://ubuntureleases.tsl.gr/12.04.2/ubuntu-12.04.2-server-amd64.iso
Verify that it has been downloaded correctly:
.. code-block:: console
- $ echo 'a8c667e871f48f3a662f3fbf1c3ddb17 ubuntu-12.04.1-server-amd64.iso' > check.md5
+ $ echo 'a8c667e871f48f3a662f3fbf1c3ddb17 ubuntu-12.04.2-server-amd64.iso' > check.md5
$ md5sum -c check.md5
-Create a 2G sparce file to host the new system:
+Create a 2G sparse file to host the new system:
.. code-block:: console
.. code-block:: console
$ sudo kvm -boot d -drive file=ubuntu_hd.raw,format=raw,cache=none,if=virtio \
- -m 1000 -cdrom ubuntu-12.04.1-server-amd64.iso
+ -m 1G -cdrom ubuntu-12.04.2-server-amd64.iso
-.. note::
+.. warning::
- During the installation, you will be asked about the partition scheme. Since
- snf-image-creator does not support LVM partitions, you are advised to create
- regular partitions.
+ During the installation, you will be asked about the partition scheme. Don't
+ use LVM partitions. They are not supported by snf-image-creator.
-When the installation is complete, you can close the QEMU window. You
-will be able to boot your installed OS and make any changes you want to it
+You will be able to boot your installed OS and make any changes you want
(e.g. install openssh-server) using the following command::
- $ sudo kvm -m 1000 -drive file=linuxmint.raw,format=raw,cache=none,if=virtio
+ $ sudo kvm -m 1G -boot c -drive file=ubuntu_hd.raw,format=raw,cache=none,if=virtio
-After you're done, become root, activate the virtual environment you have
-installed snf-image-creator in, and use *snf-mkimage* to create and upload the
+After you're done, you may use *snf-mkimage* as root to create and upload the
image:
.. code-block:: console
$ sudo -s
- $ source /path/to/snf-image-env/bin/activate
$ snf-mkimage ubuntu_hd.raw
In the first screen you will be asked to choose if you want to run the program
in *Wizard* or *Expert* mode. Choose *Wizard*.
-.. image:: /snapshots/01_wizard.png
+.. image:: /snapshots/wizard.png
-Then you will be asked to provide a name, a description, an *~okeanos* account
-and the token corresponding to this account. After that you will be asked to
-confirm the provided data.
+Then you will be asked to provide a name, a description, a registration type
+(*private* or *public*) and the authentication token corresponding to your
+*~okeanos* account. Finally, you'll be asked to confirm the provided data.
-.. image:: /snapshots/06_confirm.png
+.. image:: /snapshots/confirm.png
-Choosing *YES* will create the image and upload it to your *~okeanos* account.
+Choosing *YES* will create and upload the image to your *~okeanos* account.
-Some caveats on image creation
-==============================
+Limitations
+===========
+
+Supported operating systems
+---------------------------
+
+*snf-image-creator* can only fully function on input media hosting *Linux*
+systems. The program will detect the needed metadata and you may use it to
+upload and register other *Unix* or *Windows* images, but you cannot use it to
+shrink them or perform system preparation operations.
+
+Logical Volumes
+---------------
+
+The program cannot work on LVM partitions [#f1]_. The input media may only
+contain primary or logical partitions.
Para-virtualized drivers
------------------------
version 2.6.25 and are shipped with all the popular Linux distributions. The
problem is that if the driver for the para-virtualized disk I/O controller is
built as module, it needs to be preloaded using an initial ramdisk, otherwise
-the VM will not be able to boot.
-
-In the image creation demonstration above, we initially installed the Ubuntu
-system on a hard disk (*ubuntu_hd.raw*) that was connected on a
-para-virtualized interface (pay attention to the *if=virtio* option of the kvm
-line). Ubuntu and Debian create a generic initial ramdisk file that contains
-many different modules, including the VirtIO drivers. In many distros this is
-not the case. In Arch Linux for example, the user needs to manually add
-*virtio_blk* and *virtio_pci* drivers in */etc/mkinitcpio.conf* and rebuild the
-initial ramdisk [#f1]_ to make the virtio drivers get preloaded during boot.
-For now, *snf-image-creator* cannot resolve this kind of problems and it's left
-to the user to do it.
-
-Swap partitions
----------------
+the VM won't be able to boot.
+
+Many popular Linux distributions, like Ubuntu and Debian, will automatically
+create a generic initial ramdisk file that contains many different modules,
+including the VirtIO drivers. Others that target more experienced users, like
+Slackware, won't do that [#f2]_. *snf-image-creator* cannot resolve this kind
+of problems and it's left to the user to do so. Please refer to your
+distribution's documentation for more information on this. You can always check
+if a system can boot with para-virtualized disk controller by launching it with
+kvm using the *if=virtio* option (see the kvm command in the
+`Creating a new image`_ section).
+
+Some caveats on image creation
+==============================
+
+Image partition schemes and shrinking
+-------------------------------------
+
+When image shrinking is enabled, *snf-image-creator* will shrink the last
+partition on the disk. If this is a swap partition, it will remove it, save
+enough information to recreate it during image deployment and shrink the
+partition that lays just before that. This will make the image smaller which
+speeds up the deployment process.
+
+During image deployment, the last partition is enlarged to occupy the available
+space in the VM's hard disk and a swap partition is added at the end if a SWAP
+image property is present.
+
+Keep this in mind when creating images. It's always better to have your swap
+partition placed as the last partition on the disk and have your largest
+partition (*/* or */home*) just before that.
+
+Large temporary files
+---------------------
+
+*snf-image-creator* may create large temporary files when running:
+
+ * During image shrinking, the input media snapshot file may reach the size of
+ the original media.
+ * When bundling the host system, the temporary image file may became as large
+ as the rest of the disk files altogether.
-If you want your image to have a swap partitions, make sure this is the last
-partition on the disk. If snf-image-creator detects a swap partition in the end
-of the input media, it will remove the partition when shrinking and will save
-enough information to be able to recreate it during image deployment. This will
-make the image smaller and will speed up the deployment process.
+*/tmp* directory is not a good place for hosting large files. In many systems
+the contents of */tmp* are stored in volatile memory and the size they may occupy
+is limited. By default, *snf-image-creator* will use a heuristic approach to
+determine where to store large temporary files. It will examine the free space
+under */var/tmp*, the user's home directory and */mnt* and will pick the one
+with the most available space. The user may overwrite this behaviour and
+indicate a different directory using the *tmpdir* option. This option is
+supported by both *snf-image-creator* and *snf-mkimage*.
.. rubric:: Footnotes
-.. [#f1] https://wiki.archlinux.org/index.php/KVM#Paravirtualized_guests_.28virtio.29
+.. [#f1] http://sourceware.org/lvm2/
+.. [#f2] http://mirrors.slackware.com/slackware/slackware-14.0/README.initrd
projects / snf-image-creator / blobdiff