Use the System Load Agent

The System Load agent closely monitors the system processing load on your PacketShaper and alerts you when the load becomes too high. The standard alert is a red indicator on the info tab (PacketWise) or configuration tab (PolicyCenter). In addition, you can have an email, SNMP trap, or syslog message sent when the system load is high (such as 95%); this method requires that you create an action file — a text file of PacketWise commands. The action file can include any CLI command that can run without additional user input. See Action File Overviews for more information.

In order to use this feature, adaptive response must be enabled and you must create an agent based on the System Load template.

Create a System Load Agent

To create a System Load agent:

1. On the setup tab, click the Adaptive Response Settings link.
   
   
2. Click add. The Add Agent Entry window will open.
   
   
3. In the create a new agent from this agent template drop-down list, choose System Load.
   
   
4. Enter a unique identifying name for the new agent in the Name field.
   
   
5. If desired, change the evaluation interval, in minutes (how often the agent should measure its target).
   
   
6. Click OK and Edit Parms. This will open the Edit Agent Entry window where you can define the parameter values for your new agent.
   
   
7. If desired, modify the threshold values:
   
   RedThreshold — The value at which the status of the agent turns red, and a red action file is triggered, if present. For the System Load agent, this number is the percentage at which you consider the unit's CPU utilization to be too high. For instance, if the RedThreshold is set to 95, the agent's status will change to red when the CPU utilization is greater than 95 percent.
   
   GreenThreshold — The value at which the status of the agent turns green, and a green action file is triggered, if present. For instance, if the GreenThreshold is set to 90, the agent's status will be green when the unit's system load is less than 90 percent.
   
   
8. Click OK to save your changes.

Check the Agent Status

To check the status of the System Load agent:

1. Click the info tab. The PacketShaper’s info tab shows an icon for each agent category, and a colored status indicator for each. The System Load agent is in the Unit Health category.
   
   
2. To see the status of the System Load agent, hover your mouse over the Unit Health colored status indicator, as shown below.
   
   
   
   
3. In the pop-up window, locate the System Load agent. The value indicates the unit's CPU utilization. For example, a score of 67 indicates the unit's CPU utilization was 67 percent (33 percent idle) in the last evaluation interval.
   
   What color is its status indicator?
   
   Green — During the last evaluation interval, the Packeteer unit was not being overutilized.
   Yellow — During the last evaluation interval, the unit's CPU utilization was getting close to the red threshold. (Yellow is the range between the red and green thresholds.)
   Red — During the last evaluation interval, the Packeteer unit's CPU utilization was getting too high. If the status indicator is red, you should look at the incident report for details.
   
   If the agent has ever changed status (from green/yellow to red or from red/yellow to green, a report icon with a link to a detailed incident report will be available for that agent.
   
   
4. If there is a report for the System Load agent, click the report icon. The incident report looks similar to the one below.
   
   
   
   
   The System Load agent's incident report provides information about CPU utilization — the % idle is the amount the CPU is not being utilized. For example, if the Average % Idle is 5, the CPU utilization is 95%. The middle section contains a list of internal buffers; high numbers are indicative that the PacketShaper is under a heavy load, and are at an inappropriate level for the capacity of the unit. The bottom section lists information about the flows going through the unit. If these values are close to the unit's configuration limits, the unit can get overloaded.
   

Create an Action File

If you would like to be notified by email when the PacketShaper's system load is high (above the red threshold), you can create a command file that contains a single line: the send email command. By designating this command file as the red action file, an email will be sent when the red threshold is crossed.

Note: In order to send email notification, you must configure an SMTP server in PacketWise.

To create an action file:

1. If the info tab is currently displayed, click the Settings link; otherwise, go to the setup tab and click the Adaptive Response Settings link.

2. Click the edit button next to the System Load agent.

3. Click the browse files button. The File Browser window opens and shows the contents of the 9.258/agent/cmd directory (where action files need to be stored).

4. Click the new cmd file button. A command file window opens.

5. In the File Name field, enter a unique name for your action file up to eight characters long, including 0-9, a-z, A-Z, -,_. Spaces are not allowed. The file will automatically be assigned the extension .cmd. Example: red-load.cmd

6. In the Contents area, enter the following commands:

#Title: red action file for System Load agent
send email <address> "<subject>" ["<body>"]

where <address> is the email address of the recipient. For example:

send email raltman@test.com "System Load" "The Packeteer unit's system load is currently very high. Go to the info tab to view the incident report for the System Load agent."

Note: If you want to send an email notification to more than one recipient, repeat the send email command for each email address.

Alternatively, you can include the variables for the agent name ($agentname) and the CPU utilization ($scorevalue) in the <subject> or <body>, as the following example shows:

send email raltman@test.com "$agentname agent" "The PacketShaper's system load is currently very high ($scorevalue percent). Go to the info tab to view the incident report for the $agentname agent."

When the message is sent, the body of the email message would look something like this:

The PacketShaper's system load is currently very high (96 percent). Go to the info tab to view the incident report for the System Load agent.

7. Click save.

8. Enter the name of your action file in the Red Action File field (for example, red-load.cmd).

9. Click OK.

After the next evaluation interval, an email will be sent if and when the agent's red threshold is crossed. If you like, you can create a green action file to notify you when the System Load agent returns to a green status.