From Docker Container to Bootable Linux Disk Image

https://micromind.me/en/posts/from-docker-container-to-bootable-linux-disk-image/

by c8g • 7 years ago

93 20 7 years ago

ohiovr• 7 years ago

I would like to have something like docker where I can describe a system kind of like a docker file but output an ISO file instead of running it as a container. Does something like this exist? I can't seem to find any user friendly tools for tailoring distros. In many cases you have to mouse around. I just want to do it with a script.

dijit• 7 years ago

Correct me if I'm wrong, but this sounds a little like a buildroot. https://buildroot.org

stevekemp• 7 years ago

Packer, from hashicorp, allows you to create various image-types from a JSON configuration file.

https://www.packer.io/

It's a little bit more low-level, but I use it to build images which run under VMWare and on EC2 in AWS. I tend to just use the configuration file to install ansible inside the new instance, then configure the actual system like that.

eatonphil4• 7 years ago

I haven't used packer but it seems like operates at a different level? Dockerfiles are mostly about _provisioning_ an existing system but packer was more about getting correct configuration in place for VM providers and allowing you to specify strings to be run for provisioning.

Edit: not an edit, but I realize it's a double standard to think of Dockerfile's as anything but specifying strings for provisioning.

sansnomme2• 7 years ago

Yeah, the project is LinuxKit (also by Docker).

https://github.com/linuxkit/linuxkit/blob/master/README.md

It is mostly for cloud systems (last I checked the Alpine distro was a core dependency) and is still a bit raw but a vast improvement compared to what's currently available. Existing solutions like Buildroot/Yocto etc. have a horrendous UX, think editing Makefiles by hand while LinuxKit is Docker-style single yaml defined immutable system + go binary build tool with a unified interface.

There are also stuff like Nix and GUIX but the learning curve is non-negligible and have a lot less money driving the development.

eatonphil4• 7 years ago

I was looking at tools a while ago at Linode while trying to automate support for FreeBSD/OpenBSD/etc. The UX for different distributions (if provided at all) is disparate, confusing, and poorly documented. I ended up giving up and just building the images by hand and hosting them [0].

I've seen linuxkit a few times now but it didn't click that this is what it does.

The problem still remains that there's no good distribution-agnostic combination of boot image creator + provisioning system. The ideal situation is one tool that allows me to start with an arbitrary base distribution, provision it, and build a bootable image for the VM provider of my choice (VirtualBox, EC2, bhyve, etc.).

[0] https://github.com/eatonphil/linode_deploy_experimental

Filligree• 7 years ago

NixOS makes this nearly trivial. Any system configuration can be turned into an ISO by requesting the 'iso' attribute instead of the 'system' one.

geggam• 7 years ago

yep...

and if we go deeper you can also see isolinux has been doing this for sometime

https://wiki.syslinux.org/wiki/index.php?title=ISOLINUX

pknopf3• 7 years ago

https://godarch.com/

It integrates directly with Grub for easy booting.

eatonphil4• 7 years ago

Someone in the comments on this site posted darch [0]. Looks interesting.

[0] https://godarch.com/

agumonkey• 7 years ago

I missed that entirely.. surprising.

https://old.reddit.com/r/archlinux/comments/7uqf88/announcin...

pknopf3• 7 years ago

Author here, if anyone has any questions.

I've been using it for over a year with Ubuntu.

Here are my recipes: https://github.com/pauldotknopf/darch-recipes

pbh1012• 7 years ago

My employer built a tool which skips the disk image step and provisions a machine directly from a Docker image. The system is still maintained and in active use, though the open-source repo is a trailing fork: https://github.com/imc-trading/dock2box

polskibus• 7 years ago

Can it be used to provision VMs entirely from docker, or does it have to be bare metal only?

pbh1012• 7 years ago

In short, no: while we do run dock2box regularly to rebuild VMs, internally our VM creation process is separate from this tool.

From Docker Container to Bootable Linux Disk Image

Related Stories