Monitor Events Test

The NetScaler appliance has a set of default monitors that are automatically bound to the respective service as soon as you create the service. For example, the tcp-default monitor is bound to all TCP services and the ping-default monitor is bound to all non-TCP services. The NetScaler appliance allows multiple monitors to be bound to a service. These monitors, by default, monitor the service they are bound to, but can be configured to monitor any destination IP address, port or both. A practical example of this is a Web server which makes a call to a backend database server where, if the database server fails, you also want the Web server to be marked as Down. To be precise, the health of one service is tied to the health of another potentially related service. A service monitoring threshold is set for each service which when combined with the weight of the monitor that is bound to the service, helps you to control how many monitors must fail before you consider the service as Down. If the monitor bound to the service satisfies the threshold, then it can be inferred that the service is Up. If any monitor fails to satisfy the threshold, then the service is considered as down. Mostly services fail when there are network connectivity issues between the backend servers on the port hosting the application, or connectivity issues between the NetScaler appliance and the backend servers, or if an SSL certkey is not bound to the virtual server etc. If too many services fail, then the performance of the NetScaler appliance will begin to degrade rapidly. To keep check on the performance degradation of the NetScaler appliance, administrators should constantly monitor the number of services that are down. The Monitor Events test helps administrators in this regard 

This test monitors the monitors that are bound to a service in the NetScaler appliance and reports the number of times the monitor bound to the service had hit the threshold limit and the number of times the monitor bound to the service was up/down.

For this test to run and report metrics, the NetScaler appliance should be configured to create a Syslog file in a remote Syslog server, where the details of all interactions with the NetScaler appliance will be logged. To know how to configure a remote Syslog server for the use of the NetScaler appliance, refer to Creating a Syslog file in a remote Syslog server topic.

This test is disabled by default. To enable the test, follow the Agents -> Tests -> Enable/Disable menu sequence in the eG administrative interface, pick Citrix NetScaler VPX/MPX as the Component type, select Performance as the Test type, choose this test from the list of disabled tests list, and click on the < button.

Target of the test : A NetScaler VPX/MPX

Agent deploying the test : A remote agent

Outputs of the test : One set of results for the NetScaler appliance being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed

Host

The IP address of the host for which the test is being configured.

Port

The port at which the host listens. By default, this is NULL.

Log File Path

This test reports metrics by parsing a Syslog file. Specify the full path to the Syslog file here.

Search String

By default, the Syslog file may contain information relating to a number of servers that are inter linked with the target NetScaler appliance. In order to obtain the metrics of the target NetScaler appliance alone, specify the hostname or the IP address of the target NetScaler appliance for which the logs are to be read from the syslog file, in the Search String text box. Using this search string the information in the Syslog file may be parsed and metrics may be collected.

Search String Index

Here, specify the cursor position after which the eG agent should search for the specified Search String (or the position up to which the eG agent should ignore while searching for the specified Search String) in the syslog file. For example, if the specified Search String appears in the syslog file at the 17th position, then you may need to specify the Search String as 16.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD Frequency.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Monitor bound to the service has hit threshold limit event

Indicates the number of times the monitor bound to the service had hit the threshold limit.

Number

This measure is a good check on the health of the service.

Monitor bound to the service is down event

Indicates the number of times the monitor bound to the service was down.

Number

 

Monitor bound to the service is up event

Indicates the number of times the monitor bound to the service was up.

Number