generic/gentoo Vagrant box

How to use this box with Vagrant: 

Vagrant.configure("2") do |config|
  config.vm.box = "generic/gentoo"
  config.vm.box_version = "4.3.2"
end
vagrant init generic/gentoo \
  --box-version 4.3.2
vagrant up

v4.3.2

This version was created 7 months ago.

A build environment for use in cross platform development.

5 providers for this version.
  • hyperv
    unknown Hosted by Vagrant Cloud (1.46 GB)
  • libvirt
    unknown Hosted by Vagrant Cloud (1.73 GB)
  • parallels
    unknown Hosted by Vagrant Cloud (1.28 GB)
  • virtualbox
    unknown Hosted by Vagrant Cloud (1.78 GB)
  • vmware_desktop
    unknown Hosted by Vagrant Cloud (1.38 GB)