This guide provides formatted information drawn primarily from the MIB files written for the Server Administrator services that support the SNMP protocol.
For each MIB group that has unique variable definitions, tables are included in the last section of the section to explain the meaning of the terms.
Standards for writing MIBs are defined by the Internet Engineering Task Force (IETF). Structure of Management Information (SMI) is a standard that specifies the rules for defining the structure and type of managed objects and events in a MIB. SMIv1 is specified in Request For Comments (RFC) 1155. The Server Administrator MIB conforms to the SMIv1 standard.
SNMP is a systems management standard originally designed for network management. SNMP manages much more than networks. Information Technology (IT) professionals use SNMP for monitoring and managing computer systems and the various components and peripherals supported by their systems.
SNMP standards are defined by the Internet Engineering Task Force (IETF). SNMP version 1 was published in August 1988 and is the most commonly supported version of SNMP. SNMP version 2 was first published in May 1993, but has not gained widespread market acceptance. SNMP version 3 was recently completed and has addressed security issues that exist in version 1.
All SNMP systems consist of one or more managed systems that provide data through an SNMP agent to a management system. The management system provides a user interface to view data from the managed systems. The management system and managed systems communicate over a network (typically through User Datagram Protocol/Internet Protocol [UDP/IP]).
The management system and a managed system communicate by means of a common data schema. SNMP MIB files define the structure, type, and values of the SNMP data. While MIBs can be standardized or enterprise specific, most operating systems supply SNMP agents for the standard MIB-I and MIB-II schemas. MIB-I defines a base set of standard management information for systems implementing the Internet Protocol (IP) suite. MIB-II defines characteristics of the system, characteristics of network interfaces, and characteristics of components of the IP on the system. In addition to the standard MIBs, many hardware vendors have defined MIBs that provide management data specific to their systems and peripheral devices.
Monitored data can be retrieved through SNMP using the Get command. Typically, this command requires the host name or IP address of the target machine as well as the OID of the data to retrieve. Exact details are dependent on the operating system and the development tools being used to create the management application. The Get command has a variant known as GetNext.