|
|
This chapter briefly describes the operation of Cisco CallManager troubleshooting, diagnostics and network management using the SNMP interface.
The Simple Network Management Protocol (SNMP) is an industry-standard interface which can be used by any network management system to capture network monitoring information about Cisco CallManager.
SNMP allows system administrators and technical support engineers to remotely monitor the status of any Cisco CallManager system.
CiscoWorks2000 runs an AutoDiscovery mechanism to discover the entire network, of which Cisco CallManager may be one component. Since Cisco CallManager supports Cisco Discovery Protocol (CDP), CiscoWorks2000 can also identify the system on which Cisco CallManager is running as a Cisco CallManager device.
CiscoWorks2000 fetches CDP information by polling Cisco CallManager using SNMP. The SNMP extension agent responsible for Cisco CallManager responds to the CiscoWorks2000 interface. After the discovery process is completed, a topology map reveals all of the Cisco CallManager installations in the network.
CiscoWorks2000 also polls other Management Information Base (MIB) tables in the CISCO-CCM-MIB to fetch information required by other components, such as User Tracking (see CiscoWorks2000 Campus Manager online documentation). CiscoWorks2000 periodically polls these agents to get additional updated information.
Cisco Systems supports numerous Management Information Bases (MIBs) which organize and distribute information for a variety of network management devices. Most of the information describing your Cisco CallManager installation is provided in the form of SNMP MIB tables.
For more information on the Cisco CallManager MIB, enter CISCO-CCM-MIB into the Search box at http://www.cisco.com.
You can use the MIB table that supports Cisco CallManager to provide all of the management interfaces for monitoring and managing your Cisco CallManager network. This MIB table is periodically updated, reflecting the current status of your Cisco CallManager network.
To perform network management, you can use the CISCO-CCM-MIB to get provisioning and statistical information about Cisco CallManager, its associated devices (e.g. IP phones and gateways), and its configuration.
You can use the Cisco CallManager SNMP agent to implement the Cisco Discovery Protocol (CDP) MIB, CISCO-CDP-MIB.
This MIB enables Cisco CallManager to advertise itself to other Cisco devices on the network, allowing discovery of other Cisco CallManager installations on the network.
The Windows 2000 SNMP agent is a Windows NT-based service which is enabled when the operating system is installed. The Cisco CallManager SNMP agent supplements the Windows 2000 SNMP agent by acting as an extension agent.
 |
Caution The Windows 2000 SNMP agent provides security through the use of community names and authentication traps. The default name "public" is universally accepted in all SNMP implementations. You should change this name to limit access. |
To change the SNMP agent community name:
Step 2 Right-click on SNMP Service and select Properties.
Step 3 Select Security tab, then edit community name.
The Cisco CallManager MIB, CISCO-CCM-MIB, is managed by an SNMP agent shipped with each Cisco CallManager installation. All of the management information provided by this MIB is available to any Network Management System (NMS) via SNMP.
 |
Note The CISCO-CCM-MIB supports SNMP version 2, with the exception of the SNMP getbulk operation. |
The Cisco CallManager SNMP agent is implemented as a set of three extension agents in the form of Windows Dynamic Link Library files (DLLs). The Windows SNMP service loads these extension agents when it is started.
Two of these SNMP extension agents are used to implement the CISCO-CCM-MIB. The third one implements the CISCO-CDP-MIB.
To start the Cisco CallManager SNMP Agent:
Step 2 Double-click the Services window and select Service Control Manager.
Step 3 Select SNMP Service.
Step 4 Select Start Service from the toolbar.
The SNMP Service will start and the Cisco CallManager SNMP agent will load.
|
Note The SNMP Service is set up to start automatically when the system boots. Start the SNMP Service only if it has not started automatically. |
To stop the Cisco CallManager SNMP Agent:
Step 2 Double-click the Services window (Service Control Manager)
Step 3 Select SNMP Service
Step 4 Select Stop Service from the toolbar
The SNMP Service will stop and the Cisco CallManager SNMP agent will no longer be functional.
|
Caution Stopping the SNMP service will result in loss of data; the Network Management System will no longer be able to monitor the Cisco CallManager network. Do not stop the service except in an emergency. |
Another Windows NT-based service, Cisco SNMP Data Collector, is installed with Cisco CallManager and is started automatically upon system start-up. This service is provides a link between Cisco CallManager, the SNMP extension agents, and the Cisco CallManager database.
When the Windows NT SNMP service receives a request for a Cisco CallManager agent from a Network Management System such as CiscoWorks2000, the service passes the request onto the Cisco CallManager Agent for processing. The Cisco CallManager Agent then acts upon the request based on its type (e.g., an SNMP get, getnext or set operation).
Step 2 Double-click the Services window and select Service Control Manager.
Step 3 Select SNMP Data Collector.
Step 4 Select Start Service from the toolbar.
The SNMP Data Collector service will start and the Cisco CallManager SNMP agent will be enabled.
|
Note NOTE: The Cisco SNMP Data Collector service is set up to start automatically when the system boots. Start the Cisco SNMP Data Collector service only if it has not been able to start automatically. |
Step 2 Double-click the Services window and select Service Control Manager.
Step 3 Select SNMP Data Collector.
Step 4 Select Stop Service from the toolbar.
The SNMP Data Collector service will stop and the Cisco CallManager SNMP agent will no longer be functional.
|
Caution Stopping the Cisco SNMP Data Collector service will result in loss of data; the Cisco SNMP agent will no longer be able to get updates from the Cisco CallManager network. Do not stop the service except in an emergency. |
The Cisco SNMP Data Collector is primarily responsible for updating the information used by the SNMP agents, and it buffers the CISCO-CCM-MIB information that the agents process.
Upon startup, the Cisco SNMP Data Collector updates all the relevant information by periodically fetching data from Cisco CallManager, or the Cisco CallManager database. This updated information is based on interaction with the Cisco CallManager and other Cisco CallManager associated services.
Upon startup, the Cisco SNMP Data Collector also interacts with the CDP driver, fetching and buffering CDP-related information.
Posted: Mon Jun 12 18:22:34 PDT 2000
Copyright 1989 - 2000©Cisco Systems Inc.