What just happened?

You just created your first SNMP-based data source template. SNMP-based data source templates are the most common templates used within Cacti. In the example, you used the hrSystemProcessesMIB to template a Get SNMP data input method in order to get the actual running processes on a system. You also set a Maximum Value so Cacti is able to check the data against this value. Any data above this value will be ignored by Cacti.

Always define a good Maximum Value and Minimum Value: 

If the value is defined at 0, the SNMP poller will always fail with an error message of WARNING: Result from SNMP not valid. Partial Result: U so make sure to set a good max or min value. If you do not know the maximum value, then you can set this to U so Cacti will not check the value against a maximum or minimum value.

This basic example can be adapted to create a data template for any kind of SNMP. A good webpage to find SNMP OIDs/MIBs to poll is www.mibdepot.com. This site provides free information on almost any SNMP data that can be queried.