Re-direct to extension voice mail after dialing extension

Is there a command/feature that works as follows
I call an extension programmed auto answer or ring, There is no answer, is there a code/button/programming that can be activated by dialing a code or better still press a button (key) to have the calling extension sent to the called extension voice mail ?
Thanks to all for the help in answering my questions.

Does FreePBX/Asterisx call this feature Fail Over ? Is there a cheat sheet or similar document describing how to set up the feature ? I have looked at Wiki with out success. Thanks for the advice.

Do you have FreePBX installed? This may be the best first step.

FreePBX has voicemail and most destinations support fail over destinations.