Users Guide

Fabric OS Administrator’s Guide 207
53-1002920-02
Simple Network Management Protocol
7
Management Information Base (MIB)
SNMP Agents in the managed devices store the data about these devices in a database called
Management Information Base (MIB). The MIB is a hierarchical database, which is structured on
the standard specified in the RFC 2578 (Structure of Management Information Version 2 (SMIv2)).
The MIB is a database of objects that can be used by a network management system to manage
and monitor devices on the network. The MIB can be retrieved by a network management system
that uses SNMP. The MIB structure determines the scope of management access allowed by a
device. By using SNMP, a manager application can issue read or write operations within the scope
of the MIB.
Basic SNMP operation
Every Brocade device carries an agent and management information base (MIB), as shown in
Figure 13. The agent accesses information about a device and makes it available to an SNMP
network management station.
FIGURE 13 SNMP structure
When active, the management station can get information or set information when it queries an
agent. SNMP commands, such as get, set, getnext, and getresponse, are sent from the
management station, and the agent replies once the value is obtained or modified (Figure 14).
Agents use variables to report such data as the number of bytes and packets in and out of the
device, or the number of broadcast messages sent and received. These variables are also known
as managed objects. All managed objects are contained in the MIB.
FIGURE 14 SNMP query
The management station can also receive traps, unsolicited messages from the switch agent if an
unusual event occurs (Figure 15). For more information, refer to “Traps” on page 209.
FIGURE 15 SNMP trap
The agent can receive queries from one or more management stations and can send traps to up to
six management stations.
Agent
Management Station
SNMP
MIB
Management Station
Agent
get, getnext, set
reply
TRAP
Management Station
Agent