Wednesday, August 4, 2010
MIB - Management Information Base (An Inside Look)
In the world of routers, network management is based on the concept of a Management Information Base (MIB), a database of manageable items. In a typical MIB, you will find the system name, IP routing tables, and counts of the packets handled by each protocol, as well as counters and statistics specific to the performance of QOS.
The most popular protocol in use to manipulate MIBs is SNMP. A second version of SNMP has been developed. SNMPv2 is part of the Internet Standard Network Management Framework version 2 and is accompanied by nearly a dozen attending documents. RFC 1441 introduces the entire framework. Version 1 MIB corresponds roughly to version 1 SNMP and is documented in RFC 1155. MIB-II, the most widely implemented MIB, is documented in RFC 1213. RFC 1902 discusses version 2 MIB structure.
The MIB model is quite powerful. SNMP is a quality protocol, and many MIBs have been written for QoS settings. The most used MIB when troubleshooting QoS-related issues is the class-based QoS MIB, which provides read access to QoS configurations. This MIB also provides QoS statistics information based on the modular QoS CLI, including information regarding class map and policy map parameters.
This class-based QoS MIB is actually two MIBs: CISCO-CLASS-BASED-QOS-MIB and CISCO-CLASS-BASED-QOS-CAPABILITY-MIB.
It is not the intention here to list all available MIBs. Apart from the sheer number of them, they are also subject to change and enhancement, quickly rendering the text obsolete.
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use the Cisco MIB Locator found at the following website:
In case the Cisco MIB Locator does not support the MIB information that you need, you can obtain a list of supported MIBs and download them from the Cisco MIBs page at the following website: