Log Only sudo Failures

The sudo(8) privilege management tool is very admin-friendly in that it logs successes and failures. I don’t really care when my users successfully use sudo. I do care when they use it unsuccessfully, however. A sudo failure indicates that either the user doesn’t know their system password, or they’re trying to use forbidden commands.

sudo keeps logs. The interesting thing is, successful log messages are of priority notice, while unsuccessful attempts are of priority alert. This opens up an ea...