Learning How to Create Behavior Models - How to Use Alarms - How to Create an Alarm -
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How to Create an Alarm

As in the last scenario, you want to know which of the CriticalDevices nodes are experiencing high traffic. Now that you have created the poll 1CheckTraffic, you must create an alarm that will notify you when NerveCenter has detected high traffic.

This scenario includes the following five activities:

1. Creating a New Alarm
2. Designing a State Diagram
3. Enabling an Alarm
4. Modifying an Alarm's State Diagram
5. Adding Another State to an Alarm

Creating a New Alarm

This first activity will step you through the first stage of creating a new alarm that monitors high traffic.

 
  To create a new alarm:

1. Open the NerveCenter Client and connect to the appropriate NerveCenter Server.
2. From the Admin menu, choose Alarm Definition List.

   

   NerveCenter displays the Alarm Definition List window.

   Alarm Definition List Window

   

   Click the thumbnail above to view full-sized image.

   This window lists all the alarms in the NerveCenter database.

3. In the Alarm Definition List window, select New.

   NerveCenter displays the Alarm Definition window.

   The Alarm Definition window allows you to examine, create, or change an alarm definition. The definition is implemented through the state diagram. The next activity will step you through the process of designing the state diagram. First, you must name the alarm and limit the nodes it will monitor.

   Alarm Definition Window

   

   Click the thumbnail above to view full-sized image.

4. In the Name field, type 1HighTraffic.
5. From the Property list, select the myNodes property.

   By selecting the myNodes property, you are limiting the alarm to monitor only nodes in the CriticalDevices property group.

   In this case, limiting the nodes is redundant, because you have already limited the related 1CheckTraffic poll to this property group. If you had wanted the alarm to monitor all the nodes in your network, you would have selected the property NO_PROP.

6. From the Scope list, select SubObject.

   By selecting the SubObject scope, you are telling the alarm to monitor each port on each CriticalDevices node separately.

   Using scope in alarms is an advanced topic that is discussed in How to Use Alarm Scope in Behavior Models

7. Select Save.

You have just set the parameters of your new alarm by naming it, limiting it to the CriticalDevices property group, and setting the scope to the SubObject level. In the next activity you will design the core of the alarm, the State Diagram.

Designing a State Diagram

This next activity steps you through the process of designing a state diagram for the 1HighTraffic alarm.

 
  To design a state diagram:

1. From the toolbar at the top of the Alarm Definition window, select Add State.NerveCenter displays the State Definition window.

   State Definition Window

   

2. In the Name field, type Busy.
3. Under Severity -- Traffic, select Low.
4. Select OK.

   The State Definition window closes. An icon appears in the top left corner with the name of your new state, Busy, and a bright green color, indicating a low severity.

5. Position the Busy state icon in the middle of the state diagram.

6. From the toolbar at the top of the Alarm Definition window, select Add Transition.

   The Transition Definition window appears.

   Transition Definition Window

   

7. In the From list, select Ground. In the To list, select Busy.

   You are creating an instance when the alarm will transition from the Ground state to the Busy state.

8. In the Trigger list, select portTraffic.

   You are telling the alarm to transition to the Busy state whenever NerveCenter fires the portTraffic trigger. In the last scenario you created a poll that would fire portTraffic under certain high-traffic conditions.

   The Trigger list in the Transition Definition window contains all the predefined triggers and user-defined triggers in NerveCenter's database.

9. In the Actions area, select New Action.

   A list of alarm actions appears. You can associate one or more of these actions with each transition in a state diagram. A transition does not need an action.

10. From the alarm action list, select Beep.

    The Beep Action window appears.

    Beep Action Window

    

    Some actions require additional information. For the Beep action, the beep's frequency and duration can be changed. Notice the fields include default values.

11. In the Beep Action window, select OK.

    Beep now appears under the list of actions for this transition.

12. In the Transition Definition window, select OK.

    In the state diagram, a transition named portTraffic connects the states Ground and Busy.

    Notice the transition name, portTraffic, is the same as the trigger that causes this transition.

13. In the Alarm Definition window, select Save.
14. Select Cancel to close the window.

You have just completed creating your first alarm. In the next activity you will enable the alarm and the poll to test it out.

Enabling an Alarm

You have just completed creating the 1HighTraffic alarm. You designed the state diagram to transition the alarm from the Ground state to the Busy state when NerveCenter fires the trigger portTraffic.

This next activity will step you through the process of enabling your new 1HighTraffic alarm.

 
  To enable an alarm:

1. From the Admin menu, choose Poll List.

   

   NerveCenter displays the Poll List window.

   The 1CheckTraffic poll should have Enabled listed as On.

2. If the 1CheckTraffic poll is not enabled, turn it on.
3. From the Admin menu, choose Alarm Definition List.

   

   NerveCenter displays the Alarm Definition List window.

   Alarm Definition List Window

   

   Click the thumbnail above to view full-sized image.

   The Alarm Definition list should include the new 1HighTraffic alarm.

4. Right-click on the alarm 1HighTraffic.

   Notice the pop-up menu gives you several ways to alter the alarm without entering the Alarm Definition window.

5. Select On.

   This enables the 1HighTraffic alarm.

   You soon should hear beeps.

   ---

   Note    When the alarm is in the Busy state, NerveCenter will not send the poll out to the node again because of smart polling.

   ---

6. From the Admin menu, choose Alarm Summary.

   

   NerveCenter displays the Alarm Summary window.

   Alarm Summary Window

   

   Click the thumbnail above to view full-sized image.

   The Alarm Summary window presents information about the active alarms for the active server. The alarm summary tree on the left displays folders for the different levels of alarm severity.

   On the right is a list of all the current alarm instances. It includes the following information:

   • The name of the alarm
   • The time and date the alarm was instantiated
   • The node and subobject which had the conditions of interest
   • The name and the severity of the alarm's current state
   • The name of the trigger that caused the transition
   • The type and name of trigger generator

     In the alarm summary tree, there should be numbers beside Low, Traffic, and Severity. In the alarm instances list, 1HighTraffic probably has several alarm instances.

     You originally set the alarm's Scope to SubObject. The alarm 1HighTraffic, therefore, monitors each of your node's ports separately. Because of this there may be more than one alarm instance per node in your CriticalDevices group. If you had set Scope to Node, it would have shown no more than one instance per node.

7. Turn the 1CheckTraffic poll and the 1HighTraffic alarm to Off.

You just created, enabled, and viewed instances of your first poll. Now it is time to modify the 1HighTraffic alarm to make it easier to read and more useful. The next two activities will show you how to do that.

Modifying an Alarm's State Diagram

There may be times you will want to adjust the icons of the state diagram to make them easier to read.

This next activity will step you through the process of resizing the icons in the state diagram of the 1HighTraffic alarm.

 
  To modify an alarm's state diagram:

1. From the Admin menu, select Alarm Definition List.

   

   NerveCenter displays the Alarm Definition List window.

2. From the Alarm Definition list, select 1HighTraffic. Then select Open.

   The Alarm Definition window for 1HighTraffic appears.

   The Alarm Definition for 1HighTraffic

   

   Click the thumbnail above to view full-sized image.

3. If the alarm is on, select Off, then select Save.

   Before you can modify an alarm, you must turn it off.

   More than likely, the icons for the states and the transitions will be too small to display the entire names. You will need to resize them.

4. Right-click anywhere within the state diagram. Select Size.

   The State/Transition Size window appears.

   State/Transition Size Window

   

   The State Size and Transition Size rectangles indicate the current size of the State and Transition icons.

5. Drag the handles of the State Size rectangle to change the height and width of the rectangle. Repeat for the Transition Size rectangle.
6. Select OK.

   The State/Transition Size window closes and the icons in the state diagram are now the size you specified.

   The Alarm Definition Window for 1HighTraffic with Resized Icons

   

   Click the thumbnail above to view full-sized image.

7. Select Save.

Now that you have made the state diagram for 1HighTraffic easier to read, it is time to add another state to it. The next activity will step you through this process.

Adding Another State to an Alarm

Now that you have resized the icons in your alarm's state diagram, it is easier to read. There is, however, an even bigger problem. Currently, 1HighTraffic notifies you whenever high traffic occurs. But you expect occasional high traffic and don't want to be bothered every time there is an occasional traffic spike.

This next activity steps you through the process of adding another state to the 1HighTraffic alarm so that it will only notify you after a second occurrence of high-traffic conditions.

 
  To add another state to an alarm:

1. In the Alarm Definition window, make sure 1HighTraffic is turned off.

2. From the toolbar at the top of the Alarm Definition window, select Add State.

   NerveCenter displays the State Definition window.

3. In the Name field of the State Definition window, type TooBusy. From the Traffic severity list, select Very High. Then select OK.

   The State Definition window closes. An icon appears in the top left corner with the name of your new state, TooBusy, and a light blue color, indicating a very high severity.

4. In the state diagram, position the icon for the TooBusy state to the right of the icon for the Busy state.

5. From the toolbar at the top of the Alarm Definition window, select Add Transition.

   The Transition Definition window appears.

6. In the From list, select Busy. In the To list, select TooBusy. In the Trigger list, select portTraffic.
7. Select New Action. From the Action Alarm list, select Beep. In the Beep Action window, select OK to keep the default values and close the window.

   Beep is added to the actions list.

8. In the Transition Definition window, select OK.

   The Transition Definition window closes, and an icon for the second portTraffic transition appears between the icons for the Busy state and the TooBusy state.

   The Alarm Definition Window for 1HighTraffic with a Third State

   

   Click the thumbnail above to view full-sized image.

   You may need to adjust the state diagram to make it easier to read.

9. In the state diagram, double-click on the portTraffic transition between the Ground state and the Busy state.

   The Transition Definition window appears. Notice that Beep is still listed in the Actions list. Since you now want 1HighTraffic to notify you only when there have been two occurrences of high traffic, you must delete this action.

10. In the Actions list, select Beep.

    The Delete Action button is enabled.

11. Select Delete Action.

    A warning box appears asking if you want to delete the selected action.

    Warning about Deleting an Action

    

12. Select OK.

    The action is deleted from the Actions list.

13. In the Transition Definition window, select OK.
14. In the Alarm Definition window, select Save.

Now, when you enable the 1CheckTraffic poll and the 1HighTraffic alarm, it will only beep after the second occurrence of high traffic.

In future chapters you will explore other ways to check the persistence of a condition on your network. But, first you will need to learn how to use NerveCenter to filter traps.