Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 134)

Basic SNMP operation
Every Brocade device carries an agent and management information base (MIB), as shown in the next
figure. The agent accesses information about a device and makes it available to an SNMP network
management station.
FIGURE 16 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 as shown in the
next figure. 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 17 SNMP query
The management station can also receive traps, unsolicited messages from the switch agent if an
unusual event occurs as shown in the next figure.
FIGURE 18 SNMP trap
The agent can receive queries from one or more management stations and can send traps to up to six
management stations.
Understanding MIBs
The management information base (MIB) is a database of monitored and managed information on a
device, in this case a Brocade switch. The MIB structure can be represented by a tree hierarchy. The
root splits into three main branches: International Organization for Standardization (ISO), Consultative
Committee for International Telegraph and Telephone (CCITT), and joint ISO/CCITT. These branches
have short text strings and integers (OIDs) to identify them. Text strings describe object names, while
integers allow software to create compact, encoded representations of the names.
Basic SNMP operation
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