def auth_works?(server)
      return false unless (server && server.token && server.token.access_token)
      vspinner "Testing if authentication works using current access token" do
        Kontena::Client.new(server.url, server.token).authentication_ok?(master_account.userinfo_endpoint)
      end
    end
def auth_works?(server)
      return false unless (server && server.token && server.token.access_token)
      vspinner "Testing if authentication works using current access token" do
        Kontena::Client.new(server.url, server.token).authentication_ok?(master_account.userinfo_endpoint)
      end
    end
Check if the existing (or --token) authentication works without reauthenticating