All major open source tools like Nagios, Munin, Cacti, and others provide plugin support for MongoDB. Although it is beyond the scope of this book, operations and DevOps should be familiar with both setting up and understanding the metrics described previously to effectively troubleshoot MongoDB and preemptively resolve issues before they grow out of proportion.

mongotop, mongostat, and scripts in the mongo shell can also be used for ad hoc monitoring. One of the risks with such manual processes though is that any failure of the scripts may jeopardize our database. If there are well known and tested tools for your monitoring needs, please avoid writing your own.