Probing Algorithm and Functionality for the N1 Grid Service Provisioning System Master Server

The probing of the Master Server consists of two parts. One to probe the Apache Tomcat and a second part to probe the database.

The following steps are executed to monitor the sanity of the N1 Grid Service Provisioning System Master Server.

1. Sleeps for Thorough_probe_interval.

2. Pings the Host, which is configured in the Sun Cluster HA for N1 Service Provisioning System Master Server parameter file.

3. Connects to the Apache Tomcat via Host and Port. If the connection is successful it sends the TestCmd and tests whether the ReturnString comes back. If it fails, it is rescheduled after 5 seconds. If this fails again, then the probe will restart the Sun Cluster HA for N1 Service Provisioning System.

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   Caution –

   The ReturnString cannot be Connection refused because this string will be returned if no connection is possible.

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4. If the Apache Tomcat is operational, the probe manipulates the database table sc_test. If the connection to the database or the table manipulation is unsuccessful, the N1 Grid Service Provisioning System Master server will be restarted.

5. If the Apache Tomcat process and all the database processes died, pmf will interrupt the probe to immediately restart the N1 Grid Service Provisioning System Master Server.

6. If the N1 Grid Service Provisioning System Master Server is repeatedly restarted and subsequently exhausts the Retry_count within the Retry_interval, then a failover is initiated for the resource group onto another node. This is done if the resource property Failover_enabled is set to TRUE.