HP StorageWorks XPath OS 7.4.X MIB Reference Guide (AA-RVHEC-TE, September 2005)

XPath OS 7.4.x MIB reference guide 9
1 Understanding HP SNMP
Simple Network Management Protocol (SNMP) is a common method for monitoring and managing
network devices. The protocol promotes interoperability, as cooperating systems must adhere to a common
framework and language. Understanding the components of SNMP make it possible to use any SNMP tool
to view, browse, and manipulate HP StorageWorks switch variables as well as set up an enterprise-level
management process. Every HP StorageWorks switch supports SNMP.
This chapter discusses the following:
• Understanding SNMP basics, next
• Loading HP MIBs, page 11
NOTE: HP XPath OS 7.1.0 supports a subset of the HP Fabric OS MIBs.
Understanding SNMP basics
Every HP StorageWorks switch carries an agent and management information base (MIB), as shown in
Figure 1. The agent accesses information about a device and makes it available to a network management
station.
Figure 1 SNMP structure
When active, the management station inspects (get) or alters (set) variables when it queries an agent.
The get, getnext, and set commands are sent from the management station, and the agent replies
once the value is obtained or altered (see Figure 2). 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 2 SNMP query
When passive, the management station receives an unsolicited message (trap; see Figure 3) from the
switch agent if an unusual event occurs. See ”Loading HP MIBs” on page 11 for more information.
Figure 3 SNMP trap
The agent can receive queries from one or more management stations and can send traps to up to 6
management stations with XPath OS. Figure 4 shows the structure of a Fibre Channel SAN.
Agent
Management
Station
SNMP
MIB
Management
Station
Agent
Get, Get Next, Set
Reply
Management
Station
Agent
TRAP