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Trap Manager lets you monitor your network and specific network devices by setting alarms on network variables to determine whether a specific condition occurs. With Trap Manager, you can set multiple alarms on selected events associated with any RMON-MIB variable, as well as any private MIBs or network resources you are monitoring with the TrafficDirector Resource Monitor. You can perform such monitoring when you suspect a fault in the segment or device or want to be notified if problems develop. Using Trap Manager, you can monitor network variables as diverse as utilization and collisions for a specific segment or the failure of a network device.
An alarm is a predefined condition based on rising or falling data thresholds or both. When this condition occurs, it can generate a trap. You can set the same alarm on multiple agents and switches or multiple alarms on the same variable. When you set an alarm on a network device and a threshold condition is exceeded, the device sends a trap message to TrafficDirector or any valid trap host specified.
When you configure the agent or switch to send the trap message to a TrafficDirector console, the Alert Monitor icon on the TrafficDirector main window blinks until you acknowledge it by selecting it. You can also create a DOS batch file to take a particular action once a trap occurs.
In Trap Manager you can easily add, modify, and view alarms, as well as remove alarms you no longer need. You can also save alarm configurations in text files under names that you define. You can then retrieve these configuration files to reset or modify the alarm at any time or set the same trap on other agents or switches.
When an alarm event occurs, the agent or switch sends a trap message to the IP address of the trap hosts that you specified when adding the alarm. You can even choose to send trap messages to entire communities or to certain IP addresses based on the particular trap. In this chapter, you will learn how to use Trap Manager to monitor your network for specific conditions using its many powerful features.
An alarm is a definition of a condition you set on a variable. These variables are actually counters, and the condition you monitor is a rising or falling data value, or both. You define this condition in Trap Manager by adding an alarm. The alarm configuration not only includes the rising and falling thresholds you set, but other specifications, such as the type of trap message to send, what to include in the trap message, the action to take once the event, or trap, has occurred, and where to send the trap message (who should be notified).
When you configure an alarm, you must specify when you want the trap message generated. You can choose any of the following:
| Rising Threshold | When the current sampled value is greater than or equal to this threshold and the value of the last sampling interval was less than this threshold, the agent generates a single trap message. It does not generate another such trap message until the sampled value falls below the Falling Threshold, then rises above the Rising Threshold. |
| Falling Threshold | When the current sampled value is less than or equal to this threshold and the value at the last sampling interval was greater than this threshold, the agent generates a single trap message. It does not generate another such trap message until the sampled value rises above the Rising Threshold, then falls below the Falling Threshold. |
| Either | The agent generates a trap message when either the rising or the falling threshold is reached. |
When you are adding or modifying an alarm in Trap Manager, you can define trap messages for each threshold type--rising and falling--to include specific information that the agent sends as part of the message when the trap occurs. This information includes:
| Trap Description | This is a text string of up to 127 characters that is sent as part of the trap message to the reporting console or the IP address you specify. When the TrafficDirector console receives a trap message, the Alert Monitor blinks until you select it, then displays this text message. The default descriptions are Falling Threshold Reached and Rising Threshold Reached. |
| Value | This is the value that triggers the trap. |
| Severity | This is a relative rating of the severity of the trap. The value range is a decimal number from 0 to 99. The severity rating of a trap appears as part of the trap information displayed in the Alert Monitor. You can also pass the severity rating as an argument to batch files you execute when a trap occurs. See the section "Using Traps to Execute TrafficDirector Shell Batch Files" for more information about executing DOS batch files. |
| Program Information | You can also use DOS batch files to take a specific action when a trap occurs. You define the name and path of the file when adding the alarm, and the agent will send this information as part of the trap message. See the "Using Traps to Execute TrafficDirector Shell Batch Files" section for further details. |
Use the following procedure to start Trap Manager from the TrafficDirector main window. Once you display the Trap Manager application, you can set alarms on the agents or switches you selected to monitor selected variables for specific conditions.
Step 1 Log in to the network management station where TrafficDirector is installed, and run the TrafficDirector application.
Step 2 Select the agent, agent group, or switch that you want to set the alarm on.
Step 3 Click the Trap Manager icon or select Application>Trap Manager from the menu bar.
The Trap Manager main window (Figure 11-1) is displayed, listing all alarms set on the selected agent. Note that the name of the selected agent is displayed in the title bar.
Step 4 From this main window, you can now add, modify, view, or delete alarms that monitor and alert you of specific conditions when they occur.
Before adding an alarm, you have to specify the type of variable you want to monitor. You do this from the Trap Manager main window by selecting Type from the menu, then selecting either Domains or Resource Monitor. Your selection of variables when adding or modifying an alarm depends on the type you select.
If you choose to monitor Domains, the list in the Trap Manager main window displays all alarms set on domain-related statistics for the selected agent. When you add the alarm, you can choose from a variety of network statistics relevant to the type of network you are monitoring. For details on the variables you can set alarms on when selecting Domain, see the "Selecting Statistic Groups" section.
By selecting Resource Monitor, the list in the Trap Manager main window displays all alarms set on the proxy variables and proxy ping entries installed on the selected agent. When you add the alarm, your selection under the Variable menu includes only Resource Monitor variables. These are the proxy variables created with Resource Monitor, installed on the agent, and used to monitor network devices and private MIBs. For more about Resource Monitor and proxy variables, see the "Managing Remote Resources Using Resource Monitor" chapter.
Trap Manager lets you configure the agent to send a trap message to any valid IP address. The address must be defined as part of a community using the following procedure.
Step 1 From the Trap Manager main window, select TrapDest>List from the menu bar. The Trap Destinations window is displayed (Figure 11-2).
Step 2 Click the Add button. The Add Admin Entry window is displayed (Figure 11-3).
Step 3 Enter the IP address of the host that you want to receive the message when the trap occurs in the Target Host field.
Step 4 Assign the target host to a community by entering a name in the Community field. This could be an existing community, or you can create a new community.
Step 5 Click OK to save the entry definition.
Now that the IP address of the host has been assigned to a community, you can enter this community name in the Rising Community and Falling Community fields when you add or modify an alarm. When a rising or falling trap threshold is reached, the trap message is sent to all hosts assigned to the community.
If you selected an agent group before launching Trap Manager, the Trap Manager main window displays, by default, the alarms set on the first agent in the group. You can choose to view trap information for another agent in the group by using the following procedure.
Step 1 From the Trap Manager main window, select Scope>Agent. The Scope Agent window is displayed, containing a list of all agents in the selected group.
Step 2 Select the agent you want to view trap information for.
Step 3 Click OK. All of the alarms set on the agent you have selected are displayed in the Trap Manager main list.
You can print the contents of the list in the Trap Manager main window to either a printer or a file. To print the display, use the following procedure.
Step 1 Select File>Print from the menu bar. The Printing Options window is displayed (Figure 11-4).
Step 2 Do one of the following:
When you print directly to a printer, information is printed on the default printer. If you want to print to a different printer, you must set it as the default before you send information to print.
Step 3 Click OK.
In this section, you will learn how to monitor your network for specific conditions by setting alarms on selected statistics using Trap Manager.
Once you have launched Trap Manager from the TrafficDirector main window, you can set alarms on the agent, agent group, or switch you selected. When you want to add an alarm to an agent, use the following procedure.
Step 1 Select the agent or switch you want to set the alarm on, and launch Trap Manager as described in the previous section. The Trap Manager main window is displayed (Figure 11-1).
Step 2 Select Type from the menu and then the type of data you want to monitor. You can choose either of two data types:
Step 3 Click the New button, or select Tools>New from the menu bar. The New Alarm window is displayed (Figure 11-5).
Step 4 In the Name field, the name of a single agent or switch is automatically displayed, unless you chose an agent group before launching the application. If you selected an agent group, do the following:
multiple selected is displayed in this field instead of an agent name.
Step 5 Do one of the following:
Step 6 To the right of the Name field is the Domains field. To fill in the field, do the following:
Step 7 To the right of the Name field is the field that is named Resource Monitor. To fill in the field, do the following:
Step 8 From the menu bar, select Variable.
Trap Manager displays a list of variable statistics you can choose from (Figure 11-8). For each statistic group you select, you will see a submenu of specific variables you can select. For more about these submenus and the variables you can monitor for a specific condition, see the "Selecting Statistic Groups" section.
Use the following table to fill in the remaining fields in the New Alarm window, then go to Step 10.
| Variable OID | Specifies the unique object identifier of the variable you want to set the alarm on. To specify this variable, select Variable>Statistic Group from the menu bar. Each statistic group has a submenu of available counter variables, as shown in the "Selecting Statistic Groups" section. This field is filled in automatically after you select the variable you want to set a condition on. The variable name is displayed to the right of this field. |
| Key 1 | Specifies the host address when monitoring host statistics or the source address in the case of conversation statistics. Both are available when selecting Domain as the data type.
When selecting Resource Monitor as the type, this field displays the target host address, filled in automatically when you select a variable to monitor. |
| Key 2 | Specifies the destination address when monitoring conversation statistics, available when selecting Domain as the type. If you select Resource Monitor as the type, this field is automatically filled in with the MIB OID when a variable is selected. |
| Sample Type | Delta or Absolute. Determines whether the alarm is triggered on a change in data rate (Delta), such as a change in packets per second, or an absolute value (Absolute), such as number of packets counted. |
| Interval (sec) | Specifies the interval, in seconds, that must pass before the agent samples the data and compares it with applicable rising and falling thresholds. The value must be a decimal number. The allowed range is 1 to 3600 seconds. |
| Generate Trap When | Rising Threshold, Falling Threshold, or Either. Values must be in decimal form and must be within the range of the variable being monitored. The default threshold is Rising Threshold. |
| Threshold Type Trap Description | Specifies either or both Rising and Falling fields. Type the text string you want to be sent as part of the trap message when the threshold is exceeded. You can enter up to 127 characters. You must also complete the Value, Severity, and Program Information fields, described below, for each field type you select here. |
| Value | Specifies the value that triggers the trap. Values must be a decimal number. The ranges allowed depend on the variable selected. |
| Severity | Specifies the relative rating of the trap's severity. The value range is from 0 to 99, specified as a decimal. The severity rating of a trap appears as part of the trap message sent by the agent. |
| Program Information | Specifies the name of the DOS batch file you want to execute when a trap is detected. The default directory for the file is c:\traffdir. In this way, you can use a trap to trigger actions in TrafficDirector or DOS. |
| Rising Community | Shows that trap messages are sent to each host registered for the community specified when a rising threshold is reached. The host where you added the alarm is automatically registered. |
| Falling Community | Shows that trap messages are sent to each host registered for the community specified when a falling threshold is reached. The host where you added the alarm is automatically registered. |
| Trap Type Number | Determines the type of trap message sent. This is a standard SNMP 0 through 6 trap-type number. |
| Rising Trap Number | Specifies a number you define to identify the trap as rising type. |
| Falling Trap Number | Specifies a number you define to identify the trap as falling type. |
Step 10 Click OK to save the configuration and add the new alarm.
You can save alarm configurations in text files under names that you specify. This lets you retrieve the same configuration for use at a later time. For instance, you may want to add the same alarm on several agents that are not part of the same group, or on several switches; or modify some aspect of the existing configuration. Use the following procedure to save the alarm configuration to a file.
Step 1 From the New Alarm window, click the Save button. The Enter file name window is displayed (Figure 11-9).
Step 2 Browse for a specific path or file by using the Directories and Files lists. You can also focus your search to a specific file type by selecting the List Files of Type field and selecting a specific file type.
Step 3 Click OK to save the file under the specified name.
To retrieve an existing alarm configuration, use the following procedure.
Step 1 From the New Alarm window, select the File>Open button. The Enter file name window (Figure 11-10) is displayed.
Step 2 Browse for a specific path or file by using the Directories and Files lists. You can also focus your search to a specific file type by selecting the List Files of Type field and selecting a specific file type.
Step 3 Click OK to open the name of the file you have specified in the File Name field. The alarm configuration information is imported into the appropriate fields.
Trap Manager lets you choose a variety of variables from a number of statistic groups. You select a statistic group from the Variable menu when adding or modifying an alarm. Your available choices depend on whether you selected an Ethernet, Token-Ring, WAN, or FDDI segment. Choices that do not apply to the type of network segment are not available.
Your available choices also depend on whether you chose to work with domain or Resource Monitor proxy variables. For each group of statistics, there is a corresponding submenu of variables that you can choose to monitor. You define the alarms by setting rising or falling thresholds on these variables when adding or modifying the alarm.
The following lists the statistic menu choices. The figure associated with each menu shows the submenu for each statistic variable.
Select Type>Resource Monitor before adding, viewing, or modifying an alarm.
You can view the complete alarm configuration of any trap you have set on an agent in Trap Manager. To view a particular trap displayed in the Trap Manager main window, select the trap you want to view from the list, and click the View button, or select Tools>View from the menu bar.
Trap Manager lets you modify any of the parameters of an existing alarm configuration. You may want to change the rising or falling threshold value, destination address, or even specify a new batch file to execute when the trap occurs. To modify an existing trap, use the following procedure.
Step 1 Select the trap you want to edit from the list in the Trap Manager main window, click the Edit button, or select Tools>Edit from the menu bar.
The Edit Alarm window is displayed with the complete alarm configuration of the selected trap (Figure 11-18).
Step 2 Make changes as necessary (see the "Adding Alarms" section for descriptions of the fields on this screen and their associated values).
Step 3 Once you have finished modifying the alarm, click OK to accept the changes or Cancel to leave the configuration unchanged.
You can remove any existing traps you no longer need by selecting the trap you want to remove from the list in the Trap Manager main window, and selecting the Delete button, or selecting Tools>Delete from the menu bar. A dialog is then displayed, prompting you to confirm the deletion. Click OK to delete the trap or No to cancel the deletion.
When an alarm condition occurs, the alarm generates a trap. The agent sends the trap to the IP addresses you specified when adding the alarm. If it is a TrafficDirector console, the Alert Monitor icon on the TrafficDirector main window blinks repeatedly until you click it to display the Alert Monitor window.
You can also use traps to execute TrafficDirector shell batch files. These batch files can perform alarm functions, such as sending mail messages or printing the trap information. They can also perform actions in the network, such as changing the speed of a router. You can pass two variables from the trap to your TrafficDirector shell batch file: the agent name and the severity of the trap.
For example, you may want to automatically change the speed of a WAN router if utilization reaches a certain threshold. You can write a batch file to change the router speed if an alarm based on utilization triggers a trap. As a second example, you can generate a snapshot of the network segment if a certain threshold is reached. You can do this by writing a batch file that runs the command-line utility dvsnap when a certain threshold is reached.
Finally, you might want the PC to sound an audible alarm and flash an on-screen message if a severity 1 trap occurs. The following sample script file (Figure 11-19) sends a mail message when a trap is received:
# # Sample shell script to be executed upon trap reception # # This sends a mail message to the user showing the top hosts & conversations # echo High utilization trap received from agent $1, priority $2 > temp.$$ echo Top 10 hosts: >> temp.$$ dvsnap $1 ALL HOST 30 10 >> temp.$$ echo Top 10 conversations: >> temp.$$ dvsnap $1 ALL CONV 30 10 >> temp.$$ rm temp.$$
To use traps to execute TrafficDirector shell batch files, use the following procedure:
Step 1 Write the TrafficDirector shell batch file. Remember that you can use both the agent name and the severity level from the trap you want to use to execute the batch file.
Step 2 Create the alarm in Trap Manager as described in the "Using Trap Manager to Set Alarms" section.
Step 3 Enter the name of the TrafficDirector shell batch file in the appropriate Program Information field. You can have two separate files, one for a rising threshold and one for a falling threshold.
Step 4 Click Add to add the file. The batch file executes each time the alarm creates a trap.
To exit Trap Manager at any time, select File>Exit from the menu bar in the Trap Manager main window.
Traps can be generated by any agent in the network, even agents that are not related to TrafficDirector. The Alert Monitor trap listing shows all traps sent to the IP address of your TrafficDirector console, even if they are not RMON-related traps.
The trap list displays all the messages sent on the date shown in the date field at the top of the Alert Monitor window. Each local agent also logs traps, and you can gain access to them through an inquiry to the specific agent.
When an alarm occurs, the Alert Monitor icon at the bottom of the TrafficDirector main window flashes until you acknowledge it by clicking the icon. Click the icon a second time to display the Alert Monitor window. To view a list of traps, use the following procedure.
Step 1 Select Alert Monitor from the TrafficDirector main window. The Alert Monitor window is displayed (Figure 11-20).
Step 2 Using the buttons to the right of the date field at the top of the Alert Monitor window, select the date you want to view traps for. A list of traps recorded for that day is displayed in the list.
Step 3 If you want to view information for a specific trap, select the trap in the list. Information on that trap is displayed in beneath the list.
To delete a trap in Alert Monitor, select the trap you want to remove, then click the Delete button, or select Tools>Delete from the menu bar. A dialogue is then displayed prompting you to confirm the deletion. Select Yes to delete the trap, or No to cancel the deletion.
You can update the information in the list to show new traps. To do so, click the Refresh button.
You can print the contents of the Alert Monitor list for future reference.
Step 1 Select File>Print from the menu bar. The Printing Options window is displayed (Figure 11-21).
Step 2 Do one of the following:
When you print directly to a printer, information is printed on the default printer. If you want to print to a different printer, you must set it as the default before you send information to print.
Step 3 Click OK.
To exit the Alert Monitor, select File>Exit from the menu bar.
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