How to use this box with Vagrant:

Vagrant.configure("2") do |config|
  config.vm.box = "yungsang/coreos"
  config.vm.box_version = "0.8.5"
end

vagrant init yungsang/coreos \
  --box-version 0.8.5
vagrant up

This version was created about 10 years ago.

CoreOS

Based on CoreOS 298.0.0
Add OEM files for Vagrant and patch them
Cf.) https://github.com/coreos/coreos-overlay/pull/568
Cf.) https://github.com/YungSang/coreos-packer/tree/overlay-568
Enable the Docker daemon and open the port 4243

For VirtualBox

$ vagrant init yungsang/coreos
$ vagrant up

$ vagrant plugin install vagrant-parallels
$ vagrant init yungsang/coreos
$ vagrant up --provider parallels

2 providers for this version.

parallels
unknown	Externally hosted (github.com)

virtualbox
unknown	Externally hosted (github.com)