Managing Application Availability › How Availability Monitoring Works › Enable Availability Monitoring › Check Server Availability

Check Server Availability

The CA Application Delivery Analysis monitoring device checks server availability after it actively confirms that the application hosted by the server is unavailable. Checking server availability helps you determine whether an application availability issue is related to the application or the server which hosts the application.

If you do not want to actively check the availability of the servers that host the application, disable availability monitoring on each assigned server. By default, server availability monitoring is enabled.

To monitor the availability of a load-balanced application, in addition to checking server availability, you must also specify the minimum number of servers that must be available. For example, with a load-balanced application, the load balancer may not share the application load across all of its servers, so it is only necessary to verify that a minimum number of servers are hosting the application.

Note: Server availability is not checked when the application has a status of Available, therefore, it is possible for all of the assigned servers in a load-balanced application to have a status of Available while some of the servers are not actually available.

Follow these steps:

1. Click the Administration page.
2. Click Data Monitoring, Applications in the Show Me menu.
3. Scroll to the Application List, select a user-defined application, and click Edit.

   Application Properties opens.

4. Click Assignments.
5. (Optional) If the servers that host the application are part of a load-balanced farm, specify the minimum number of servers that must be available by following these steps:
   1. Select Servers support the application in a load balanced farm. If this option is unavailable, click Properties and enable application availability monitoring.
   2. Type a value for the Minimum servers required for the application to be considered available.
6. Click OK.
7. Click the link to synchronize monitoring devices with the current client network, server subnet, and application definitions on the management console.

   Monitoring devices temporarily stop monitoring application performance during synchronization. To minimize interruptions to monitoring, complete all of your changes before synchronizing monitoring devices.

More information:

Edit a Server