You can use Simple Network Management Protocol (SNMP) together with Netscape management information bases (MIB) and network management software, such as HP OpenView, to monitor your servers in real time just as you monitor other devices in your network. If you're using Windows NT, SNMP service is built in, and you use the Windows NT Control Panel to manage it. If you're using Unix or another platform that doesn't support the SNMP multiplexing protocol (SMUX), you can use Netscape Console to manage the SNMP service Netscape provides.
Setting Up SNMP on a Netscape Server
Using a Proxy SNMP Agent
Reconfiguring the SNMP Native Agent
Enabling and Starting the SNMP Master Agent
Configuring the SNMP Master Agent
Enabling the Subagent
The subagent gathers information about the server and passes the information to the server's master agent. Every Netscape server, except for the Administration Server, has as subagent.
The master agent exchanges information between the various subagents and the NMS. The master agent is installed with Netscape Console Administration Server.
Figure 7.1 Interaction between the a network management station and a host computer.
A managed entity, such as a server, stores variables pertaining to network management. Variables that the master agent can access are known as managed objects. Managed objects are defined in a tree-like hierarchy known as a server's management information base (MIB).
Each Netscape server has its own management information base (MIB). All Netscape MIBs are located at
The Netscape Console Administration Server MIB is a file named
GET and SET are two types of messages defined by SNMP. GET and SET messages are sent by an NMS to a master agent. You can use one or the other, or both with Netscape Console Administration Server. Messages sent by the server to the NMS are known as traps. The following examples best illustrate the use of GET, SET, and trap messages.
The master agent forwards the message to the appropriate subagent.
The subagent retrieves the data or changes the variable in the MIB.
The subagent reports data or status to the master agent, then the master agent forwards the message back (a GET message) to the NMS.
The NMS displays the data textually or graphically through its network management application.
The master agent sends a message, or trap reporting the event to the NMS.
The NMS displays the information textually or graphically through its network management application.
If so, does your native SNMP agent support SMUX communication? (If you're using the AIX platform, your system supports SMUX.)
Table 7.1 Overview of procedures for enabling SNMP master agents and subagents.
Enable the subagent for each server installed on the system.
Start the master agent.
Start the proxy SNMP agent.
Restart the native agent using a port number other than the master agent port number.
Figure 7.2 Using a proxy server when you're running a native SNMP agent.
To install the SNMP proxy agent, edit the CONFIG file (you can give this file a different name), located in plugins/snmp/sagt in the server root directory, so that it includes the port that the SNMP daemon will listen to. It also needs to include the MIB trees and traps that the proxy SNMP agent will forward.
Here is an sample CONFIG file:
AGENT AT PORT 1161 WITH COMMUNITY public SUBTREES 1.3.6.1.2.1.1, 1.3.6.1.2.1.2, 1.3.6.1.2.1.3, 1.3.6.1.2.1.4, 1.3.6.1.2.1.5, 1.3.6.1.2.1.6, 1.3.6.1.2.1.7, 1.3.6.1.2.1.8 FORWARD ALL TRAPS;
To start the proxy SNMP agent, at the command prompt, enter:
# sagt -c CONFIG&
After starting the proxy SNMP agent, you need to restart the native SNMP daemon at the port you specified in the CONFIG file. To restart the native SNMP daemon, at the command prompt, enter
# snmpd -P <port number specified in the CONFIG file>
# snmpd -P 1161
smux 1.3.6.1.4.1.1.1450.1 "" <IP_address> <net_mask>
IP_address is the IP address of the host the subagent is running on, and net_mask is the network mask of that host.
To configure the master SNMP agent manually:
Check to see if there is an SNMP daemon (snmpd) running on port 161.
If an SNMP daemon is running, make sure you know how to restart it and which MIB trees it supports. Then kill its process. Edit the CONFIG file located in plugins/snmp/magt in the server root directory.
If an SNMP daemon is running, make sure you know how to restart it and which MIB trees it supports. Then kill its process.
(Optional) Define sysContact and SysLocation variables in the CONFIG file.
The CONFIG file defines the community and the manager that master agent will work with. The manager value should be a valid system name or an IP address. Here is an example of a basic CONFIG file:
COMMUNITY public ALLOW ALL OPERATIONS MANAGER <your_manager_station_name> SEND ALL TRAPS TO PORT 162 WITH COMMUNITY public
You can edit the CONFIG file to add initial values for sysContact and sysLocation which specify the sysContact and sysLocation MIB-II variables. Note that the strings for sysContact and sysLocation in this example are enclosed in quotes. Any string that contains spaces, line breaks, tabs, and so on must be in quotes. You can also specify the value in hexadecimal notation.
COMMUNITY public ALLOW ALL OPERATIONS MANAGER nms2 SEND ALL TRAPS TO PORT 162 WITH COMMUNITY public INITIAL sysLocation "Server room 501 East Middlefield Road Mountain View, CA 94043 USA" INITIAL sysContact "John Doe email: <jdoe@netscape.com>"
Once you have installed the SNMP master agent, you can start it manually or by using Netscape Console.
To start the master agent manually, enter the following at the command prompt:
# magt CONFIG INIT&
To start a master agent on a nonstandard port, use one of two methods:
TRANSPORT extraordinary SNMP OVER UDP SOCKET AT PORT 11161
After editing the CONFIG file manually, you should start the master agent manually by typing the following at the command prompt:
To start the SNMP master agent using Netscape Console:
In Netscape Console, open the console for the Administration Server that is running the management software.
In the Administration Server Console, choose Tasks, then double-click Configure SNMP Master Agent.
Click Start.
A community string is a text string that an SNMP agent uses for authorization. This means that a network management station would send a community string with each message it sends to the agent. The agent can then verify whether the network management station is authorized to get information. Community strings are not concealed when sent in SNMP packets; strings are sent in ASCII text.
To add, modify, or remove a community string:
In the Administration Server Console, click Tasks.
Click the Configure SNMP Master Agent button, then click Communities.
.
Click Add, Edit, or Remove as necessary.
Enter community string information as necessary:
:
Community. Enter a community string you want to add or edit. A community string is a password that an SNMP agent uses for authorization. GET and SET. Choose this option if you want to use this community string for requesting data or replying to messages, and for setting variable values. GET only. Choose this option if you want to use this community string only for requesting messages or replying to messages. Click OK.
SET only. Choose this option if you want to allow this community string only for setting variable values.
An SNMP trap is a message the SNMP agent sends to a network management station. For example, an SNMP agent sends a trap when an interface's status has changed from up to down. The SNMP agent must know the address of the network management station so that it knows where to send traps. You can configure this trap destination for the SNMP master agent from Netscape Console. You can also view, edit, and remove the trap destinations you have already configured. When you configure trap destinations using Netscape Console, you are actually editing the CONFIG file.
In the Administration Server Console, Click Tasks.
Click the Configure SNMP Master Agent button, then click Managers.
Enter Manager information as necessary:
Manager Station. Enter a valid system name or an IP address for the NMS. Trap Port. Enter the port number the NMS uses to listen for traps. (The default is 162.) With Community. Enter the community string you want to use in the trap. A community string is a password that an SNMP agent uses for authentication Click OK.
"SNMP Basics"