SNMP and the Network Administrator

When SNMP has been installed on a server, a network administrator can use it to:

• • View and change parameters in the LAN Manager and MIB II MIBs
• • View and change parameters for any WINS servers on the internetwork
• • Monitor DHCP servers

Installing SNMP also allows the network administrator to use the Performance Monitor to look at TCP/IP, FTP, and WINS counters.

A network manager can use SNMP management tools to obtain information from any of the MIBs that are installed on the Windows NT computer.

Once SNMP has been installed on a Windows NT computer, it automatically starts when the computer is started.

Using SNMP With Other Windows NT Tools

When you install DHCP and WINS servers, the DHCP Manager and WINS Manager are added to the Network Administrator group in Program Manager. You can use these tools to view and to change information for DHCP and WINS servers. Similarily, you can use the FTP Server service to configure FTP servers.

You can also use Performance Monitor to monitor WINS servers, FTP Server service traffic, and each of the different elements that make up the TCP/IP protocol suite.

Why would you want to use SNMP to view and change any of this information? Because some of the data cannot be changed except by using SNMP or by editing the Registry. All of the WINS configuration parameters can be set using SNMP.

Caution

You can impair or disable Windows NT if you make incorrect changes in the Registry while using Registry Editor. Whenever possible, use WINS Manager or SNMP to make configuration changes, rather than using Registry Editor. If you make errors while changing values with Registry Editor, you will not be warned, because Registry Editor does not recognize semantic errors.

For more information about DHCP, see Chapter 13, "Installing and Configuring DHCP Servers," in the Windows NT Networking Guide.

For more information about WINS, see Chapter 14, "Installing and Configuring WINS Servers," in the Windows NT Networking Guide.

For more information about Performance Monitor, see Chapter 17, "Using Performance Monitor with TCP/IP Services," in the Windows NT Networking Guide and the index in Optimizing Windows NT.

For information about which WINS parameters can be set using SNMP, see the section "MIB Object Types for Windows NT" in Appendix A.

Turning SNMP On and Off

You can start and stop SNMP from the MS-DOS console window or by using the Services icon in Control Panel. Since SNMP starts when you install it, you will usually not need to start SNMP. If you stop SNMP, it does not start when you restart your computer. If SNMP is already running on the computer, you need to stop it before you can restart it.

One reason to stop and start SNMP is to configure error logging of the SNMP agent. This is settable only from the MS-DOS console window, not from the Control Panel.

The syntax of this command is:

net start snmp [/LOGLEVEL:level] [/LOGTYPE:type]

where

/LOGLEVEL:level

determines which events to log. The higher the level number, the more events will be logged. The default for level is 1; the range is 1-20.

/LOGTYPE:type

determines where the log will be created. The possible values are 2 for file and 4 for eventlog. The default is 4. To log events in both a file and the eventlog, use the value 6. The file option creates the file \<WINDIR>\SYSTEM\SNMPDBG.LOG.

You can type

net help start snmp

in the MS-DOS console window to see how to configure error logging of the SNMP agent.

A second reason to stop and restart SNMP is to load new extension-agent DLLs. You can do this either from the MS-DOS console window using "NET STOP SNMP" and "NET START SNMP" or from the Control Panel Services option. Changes made from the MS-DOS console window are not reflected in the Control Panel Services option.

Stopping a service cancels any network connections the service is using.

You must be logged on as a member of the Administrators group to start or stop the SNMP service.

SNMP Utilities

This table describes the SNMP utilities and files that are available on the Windows NT Resource Kit CD.