11:02 p.m.
As we get closer to putting disposable clients into production, we need
a way to have updated images for those clients. I don't think this is
news to anyone since the topic has come up several times before but now
there's a bit more urgency :)
In my mind, we have the following requirements:
- Produces qcow2 images that work with testcloud
- can be run in an automated way
- allows adding/changing/customizing packages contained in image
- allows arbitrary repos to be specified
and the following "nice to have" things:
- can build branched and rawhide images
- builds images from scratch using only things provided by releng
- written in python
- builds more than qcow2 for some future-proofing
- can run well in a VM
Is there anything that I missed?
As far as I know, we're looking at two options right now:
taskotron-vmbuilder and imagefactory. I've put together a list of
the pros and cons that I know of for both tools. Thoughts on which
direction to take would be appreciated.
Tim
taskotron-vmbuilder [1] is a PoC system kparal built around
virt-builder [2]. Images are specified in a yaml file and instead of
building those images from scratch "It takes cleanly prepared, digitally
signed OS templates and customizes them".
[1] https://bitbucket.org/fedoraqa/taskotron-vmbuilder
[2] http://libguestfs.org/virt-builder.1.html
pros:
- already does almost everything we need
- fits all requirements
- builds quickly
- well supported
cons:
- requires blobs which are out of our control
* yes, I know who does the work behind virt-builder. My concern
isn't with him, it's the general concept that I don't like. This
also gets into the fact that we would have pretty much no control
over timing of release for the base images.
- limited support for rawhide and branched releases
- limited support for non-server spins
- output images are large in size
- virt-builder is not written in python
imagefactory [3] is a system for building os images and potentially
shipping those images to various cloud systems. Images are specified
with a kickstart file and an xml template descriptor. Imagefactory
builds images from scratch, essentially using the kickstart to run an
install inside a VM and processing that install into the desired image
type.
[3] http://imgfac.org/
pros:
- used by releng to create Fedora cloud images
- builds images from packages: no blobs that we don't have control over
- already has a mostly-complete RESTful api that can list images and
trigger new builds
- can support almost all spins; anything that can be represented in a
kickstart
- written in python
cons:
- not as fast as virt-builder
- somewhat more complex than virt-builder
- when something goes wrong, debugging can be difficult due to how the
tool works
- we may be somewhat on our own to fix issues if releng is not hitting
similar problems
- may not run well in a VM (would need nested virt)