Template:FAQ:Coding 02

That's typically the hardest bit of implementing a new MIB module, and is the one thing that 'mib2c' can't help with. It very much depends on the MIB variable concerned (and often the underlying operating system as well).

Relatively few MIB modules are completely self-contained, with all the information held internally within the agent, and all updates being done via SNMP requests. Such MIB modules can be implemented fairly easily.

More commonly, the agent needs to provide an SNMP-based interface to information held elsewhere, perhaps in the operating system kernel or some other application. Handling this is much more complex - since a lot depends on what mechanisms are provided for retrieving (and possibly updating) this information.

See the existing MIB modules in the Net-SNMP source tree for various examples of assorted approaches to this task.