We are goint to try running container directly on a container-runtime without container engine. Will be using crun for this experiment. We will be using ubuntu 18.04 for setting up the crun. Since we are setting up the crun from source, installation of crun should be independent of distro provided that the required build packages are available. I have given package details for ubuntu / debian. Similar package has to be installed if you are using other distribution. You can try static build, then no build dependency needs to be met.

Setting up crun in linux machine

  1. Install the required build requirement

     sudo apt install -y autoconf automake autotools-dev libtool pkg-config \
 libcap-dev libseccomp-dev libyajl-dev
 ./configure
 make

  2. You can generate static build as-well

     nix build -f nix/

Creating container using crun

  1. Download alpine rootfs and extract it (can be any rootfs)

     wget https://dl-cdn.alpinelinux.org/alpine/v3.13/releases/x86/alpine-minirootfs-3.13.0-x86.tar.gz
 mkdir rootfs && tar -xvf alpine-minirootfs-3.13.0-x86.tar.gz -C rootfs

  2. Generate the config.json file

     ./result/bin/crun --rootless=1 spec

  3. Run the container

     ./result/bin/crun --rootless=1 run alpine