Why isn't vagrant private network not set up when configured within provider block?

Question

I'm trying to understand why putting the network options in the provider block of Vagrantfile doesn't work. For example, this seems to work:

config.vm.define "mymachine" do |vbox_config|
  vbox_config.vm.network :private_network, ip: "10.10.10.10"

  vbox_config.vm.provider :virtualbox do |vb|
    vb.ssh.forward_agent = true
  end
end

but this doesn't work (network is not accessible):

config.vm.define "mymachine" do |vbox_config|

  vbox_config.vm.provider :virtualbox do |vb|
    vb.ssh.forward_agent = true
    vb.vm.network :private_network, ip: "10.10.10.10"
  end
end

It seems like I would want to set the network options to be specific to a provider and structure the Vagrantfile like the latter. Any ideas why it's not working?

Answer 1

If you want to set non-provider specific configuration inside a provider block you have to use a different syntax:

config.vm.define "mymachine" do |vbox_config|

  vbox_config.vm.provider :virtualbox do |vb, override|
    override.ssh.forward_agent = true
    override.vm.network :private_network, ip: "10.10.10.10"
  end
end

Indeed, the first argument is for provider specific configuration (e.g. vb.customize), while the second is for overrides. Please see the documentation for more information.