Welcome back for another episode of the ABC's of NSM.  What's NSM you say?  We'll go with Network and System Management, but you could throw Security in there as well.  We'll work our way through the alphabet over the next several weeks looking at tools and concepts along the way for all the administrators out there.  By the way, you can thank Joe for the format & Don for the title (I couldn't for the life of me come up with one.)

Cacti is extremely flexible in the way data can be gathered and displayed.  SNMP is the traditional collection method, but you could also write scripts that Cacti can call to populate the RRD files with data.  Also, all your work can be saved as templates, so you can re-use your work within the system, and export any work you do and share with the DevCentral community!  The web interface is clean and customizable, the user administration features are robust, and the plugin architecture supports great work like the Network Weathermap.  When building a weathermap, the links are bound to an RRD file, so in the case of this image, a traffic in/out RRD file is referenced, and the line is colored based on the percentage of the link.  If you had to look at the throughput manually for all the links to the left, could you piece together what's happening on your network as quickly as you can by a quick glance at the map?  Not me.  Oh, another cool thing about the weathermap is by mousing over the link, you get a nice 24-hour historical graph of the link's performance.