Automatic packing of server-side product as Docker and OVA image

Question

We develop a server-side solution and to ease its deployment we would like to provide our cutomers with two options:
1. Docker image
2. VM image in OVA format

The images should be automatically created by our build machine.
As of today, we use packer for this purpose. First we create docker image and then update that image in preconfigured virtual machine image (using 'virtualbox-ovf' builder). This works pretty well, but there are some problems with this solution.
First, our vm includes docker framework and two OSes (host's and docker's), so our VM image is ~twice bigger than docker. Second, to base our solution on another linux distro, we should manually configure new VM machine.
We are looking for 'Dockerfile'-style solution to create and configure VM automatically and then export it in OVA format. 'virtualbox-iso' builder is the obvious way to do this, but the building process will be much longer.

Answer 1

If you are willing to use Debian as your base OS then you could look at TurnKey Linux's TKLDev. It's probably a bit of a learning curve initially but it's a pretty cool thing IMO (although I'm very biased - see below disclaimer). TKLDev will build you a TurnKey (Debian based) ISO with your software installed on top. Then using Buildtasks you can convert the ISO to OVA, VMDK, LXC, Docker, OpenStack, etc...

Unfortunately Buildtasks is not very well documented but significant chunks of it are in bash so if you are handy with a Linux commandline you could work it out. Otherwise ask on the TurnKey forums.

The initial development (from Packer to TKLDev) may take a little while, but once the heavy lifting is done the creation of an ISO (in a guest VM on a moderm multicore CPU PC) takes about 10-15 mins and the OVA probably another ~5; Docker another ~5.

If you wanted to make it build automatically then you could use a hook to trigger a fresh TKLDev build (including the buildtasks image creation) everytime a commit was made to a repo. I know that git supports this but I assume that other version control systems allow something similar.

Also if the appliance that you are making is open source then perhaps it could be added to the TurnKey Linux library?

Disclaimer: I work with TurnKey Linux. :)

FWIW this is essentially the process we use to create our library of appliances in most virtualisation formats known to human kind!