Create an Agent that Monitors a Class Variable
You can create an adaptive response agent to monitor any class measurement
variable available in PacketWise. For example, you can monitor application
availability (app-availability%), average round trip time (avg-round-trip-time),
network delay (network-delay-avg), or packet exchange time (pkt-exchange-time-avg)
of a traffic class. See Measurement
Variables for a complete list.
In this example, we will create a new agent called Total Delay. This
agent will monitor the total-delay-avg measurement variable (average number
of milliseconds to complete the class' transactions; includes network
delay and server delay) for a specific traffic class. When the class'
total delay exceeds a predefined threshold, the adaptive response feature
will alert you that a threshold has been exceeded. 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 red threshold is crossed; 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 create agents, the adaptive
response feature must be enabled.
Create a New Agent
To create an agent for a class measurement variable:
- On the setup tab, click the Adaptive Response Settings
link.
- Click add. The Add Agent Entry window will open.
- Click the create a new agent from this agent template drop-down
list, and choose Class ME Variables.
- Enter a unique identifying name for the new agent in the Name
field, for example Citrix Delay.
- Click OK and Edit Parms. This will open the Edit Agent
Entry window where you can define the parameter values for your
new agent.
- In the ClassName field, enter the name of the class to be
monitored (for example, Inbound/Citrix).
- In the MeVariableName field, enter the measurement variable
to be monitored (total-delay-avg). For a complete list of measurement
variables you can use, see Measurement
Variables; you can select any variable in the Common and Class categories.
- Specify 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 a Total
Delay agent, this number represents the average delay in milliseconds.
For instance, if the RedThreshold is set to 500, the agent's status
will change to red when the class' average network and server delay
is over 500 ms in the MeDuration (see step 11 below).
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 300, the agent's status will be green
when the average delay is less than 300 ms in the MeDuration.
- If desired, change the values for GreenOperator and/or RedOperator.
In this example, the values for GreenOperator (LT—less than) and
RedOperator (GT— greater than) are appropriate. This agent will
have a red status when the current value of the measurement variable
is greater than (GT) the RedThreshold value and a green status when
the current value is less than (LT) the GreenThreshold value. You may
want to change the values to GTE (greater than or equal to) and LTE
(less than or equal to).
- If desired, change the evaluation interval, in minutes (how
often the agent should measure its target.)
- Specify the MeDuration, the period of time over which measurements
will be looked at.
The MeDuration can be different from the evaluation interval. For example,
suppose you set the evaluation interval to 5 minutes and the MeDuration
to 60 minutes. The agent will look at the last hour of measurement data
every five minutes to see if the red threshold has been exceeded. At
12:00, the agent would analyze data collected between 11:00 and 12:00;
at 12:05, the agent would analyze data collected between 11:05 and 12:05;
and so forth.
- Click OK to save your changes.
After creating the agent, you will want to monitor it to see if the average
network and server delay in the class was excessive.
Check the Agent Status
To check the status of the Total Delay agent:
- Click the info tab. The PacketShaper’s info tab shows
an icon for each agent category, and a colored status indicator for
each. The Total Delay agent is in the User Event Emulation category
(the last one).
- To see the status of each individual agent in the User Event Emulation
category, hover your mouse over the colored status indicator, as shown
below.
- In the pop-up window, locate the Total Delay agent that you defined.
The value (for example, 1970) indicates the number of milliseconds of
the class' average network and server delay during the MeDuration.
What color is its status indicator?
Green — During the MeDuration, delay in the class was at
an acceptable level (less than the green threshold).
Yellow — During the MeDuration, the score (the value of
the measurement variable) was between the red and green thresholds.
Red — During the MeDuration, delay in the class was at an
unacceptable level (more than the red threshold). 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 report will be available for that agent.
- If there is a report for the Total Delay agent, click the report icon.
The incident report appears in a separate browser window.
Create an Action File that Sends an Email Notification
If you would like to be notified by email when a class' delay is excessive
(that is, 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 that sends an email notification:
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 Total
Delay 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,
AZ, -,_, and . (period). Spaces are not allowed. Example: appdelay
6. In the Contents area, enter the following commands:
#Title: red action file for Total Delay agent
send email <address> "<subject>" ["<body>"]
where <address> is the email address of the recipient. For
example:
send email raltman@test.com "Citrix is too slow" "The
average delay (server plus network) for Inbound/Citrix was at an unacceptable
level."
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 ($agentname),
class name ($class-id), value of the measurement variable ($me-value),
and the red threshold ($RedThreshold) in the <subject> or
<body>, as the following example shows:
send email raltman@test.com "$agentname agent" "The
average delay (server plus network) of the $class-id class was $me-value
ms. This is over the red threshold ($RedThreshold ms). Go to the info
tab to view the report for the $agentname agent."
When the message is sent, the body of the email message would look something
like this:
The average delay (server plus network) of the Inbound/Citrix class
was 70 ms. This is over the red threshold (60 ms). Go to the info tab
to view the report for the Citrix Delay agent.
7. Click save.
8. Enter the name of your action file in the Red
Action File field (for example, appdelay.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 Total Delay agent returns to a green
status.
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