ZyXEL Communications P-870HW-I User Manual

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P-870HW-I1 User’s Guide
Chapter 16 Remote MGMT
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An SNMP managed network consists of two main types of component: agents and a manager. 
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, node port status etc. 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.
16.1.4.1  Supported MIBs
The ZyXEL Device supports MIB II as defined in RFC 1213 and RFC 1215. The focus of the 
MIBs is to let administrators collect statistical data and monitor status and performance.
16.1.4.2  SNMP Traps 
The ZyXEL Device will send traps to the SNMP manager when any one of the following 
events occurs:
Table 92   SNMPv1 Traps
TRAP #
TRAP NAME
DESCRIPTION
0
coldStart (defined in RFC-1215)
A trap is sent after booting (power on).
1
warmStart (defined in RFC-1215)
A trap is sent after booting (software reboot).
6
whyReboot (defined in ZYXEL-
MIB)
A trap is sent with the reason of restart before 
rebooting when the system is going to restart (warm 
start).
6a
For intentional reboot :
A trap is sent with the message "System reboot by 
user!" if reboot is done intentionally, (for example, 
download new files, CI command "sys reboot", etc.).
6b
For fatal error : 
A trap is sent with the message of the fatal code if the 
system reboots because of fatal errors.