Vagrant delete Chef node and Client on destroy

Vagrantfile

module Vagrant
   module Provisioners
    class ChefClient
      def cleanup
        env[:ui].info "Attempting to remove client #{env[:vm].config.vm.host_name}"
        `knife client show #{env[:vm].config.vm.host_name}`
        if $?.to_i == 0
          env[:ui].info "Removing client #{env[:vm].config.vm.host_name}"
          `knife client delete #{env[:vm].config.vm.host_name} -y`
        end
        env[:ui].info "Attempting to remove node #{env[:vm].config.vm.host_name}"
        `knife node show #{env[:vm].config.vm.host_name}`
        if $?.to_i == 0
          env[:ui].info "Removing node #{env[:vm].config.vm.host_name}"
          `knife node delete #{env[:vm].config.vm.host_name} -y`
        end
      end
    end
  end
end

@FractalizeR I was having similar issue, I read most of conversations and no luck with any workaround provided. You may got here as well (hashicorp/vagrant#2476)

Then I tried similar thing, I removed/uninstall vagrant and install it again. However, I got another error, which sounds better:

stderr: WARNING: No knife configuration file found ERROR: Your private key could not be loaded from /etc/chef/client.pem

It might help.