August 24, 2018

I encountered the same problem as well. I was installing a fixed version using chef and the problem was exactly as the OP has.

To solve it, I searched for the available packages

apt-cache madison docker-ce

It gave me an output like this

docker-ce | 18.06.1~ce~3-0~ubuntu | bionic/stable amd64 Packages
docker-ce | 18.06.0~ce~3-0~ubuntu | bionic/stable amd64 Packages
docker-ce | 18.03.1~ce~3-0~ubuntu | bionic/stable amd64 Packages
W: Target Packages (stable/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list.d/Docker.list:1 and /etc/apt/sources.list.d/docker-stable.list:1

And I picked most up-to-date version from the list and it worked.

August 20, 2018

On the new version of Vagrant, answer by @Amos Shapira gets stuck in an infinite loop. The reason for that is each call to vagrant plugin install also processes the Vagrantfile and when processed executes the code relating to installing the plugin again and again and so on.

Here is my solution which avoids the loop.

# Plugins
# Check if the first argument to the vagrant
# command is plugin or not to avoid the loop
if ARGV[0] != 'plugin'

  # Define the plugins in an array format
  required_plugins = [
    'vagrant-vbguest', 'vagrant-hostmanager', 
  plugins_to_install = { |plugin| not Vagrant.has_plugin? plugin }
  if not plugins_to_install.empty?

    puts "Installing plugins: #{plugins_to_install.join(' ')}"
    if system "vagrant plugin install #{plugins_to_install.join(' ')}"
      exec "vagrant #{ARGV.join(' ')}"
      abort "Installation of one or more plugins has failed. Aborting."


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