I mentioned eariler I have ecountered problem when installing some gem like this

Here is a way to prevent failure stops the chef provision: use ignore_failure

      gem_package "mail" do
        gem_binary '/opt/sensu/embedded/bin/gem'
        ignore_failure true
        action :install
      end

You can always go back and reinstall the gem later. You don’t want to 10 to 20 min provisioning exercise aborted due to a temporay ruby gem installation issue.