ZyXEL Communications P-2612HW Series User Manual page 363

An agent is a management software module that resides in a managed device (the
ZyXEL Device). An agent translates the local management information from the
managed device into a form compatible with SNMP. The manager is the console
through which network administrators perform network management functions. It
executes applications that control and monitor managed devices.
The managed devices contain object variables/managed objects that define each
piece of information to be collected about a device. Examples of variables include
such as number of packets received and node port status. A Management
Information Base (MIB) is a collection of managed objects. SNMP allows a
manager and agents to communicate for the purpose of accessing these objects.
SNMP itself is a simple request/response protocol based on the manager/agent
model. The manager issues a request and the agent returns responses using the
following protocol operations:
• Get - Allows the manager to retrieve an object variable from the agent.
• GetNext - Allows the manager to retrieve the next object variable from a table
or list within an agent. In SNMPv1, when a manager wants to retrieve all
elements of a table from an agent, it initiates a Get operation, followed by a
series of GetNext operations.
• Set - Allows the manager to set values for object variables within an agent.
• Trap - Used by the agent to inform the manager of some events.
Supported MIBs
The ZyXEL Device supports MIB II, which is defined in RFC-1213 and RFC-1215.
The focus of the MIBs is to let administrators collect statistical data and monitor
status and performance.
SNMP Traps
The ZyXEL Device will send traps to the SNMP manager when any one of the
following events occurs:
Table 122 SNMP Traps
TRAP # TRAP NAME
0 coldStart (defined in RFC-
1215)
1 warmStart (defined in RFC-
1215)
4 authenticationFailure (defined
in RFC-1215)
6 whyReboot (defined in ZYXEL-
MIB)
P-2612HW Series User's Guide
Chapter 20 Remote Management Configuration
DESCRIPTION
A trap is sent after booting (power on).
A trap is sent after booting (software reboot).
A trap is sent to the manager when receiving
any SNMP get or set requirements with the
wrong community (password).
A trap is sent with the reason of restart before
rebooting when the system is going to restart
(warm start).
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