Figure 17 shows an overview of the network in this configuration:
Figure 17. Failover functionality
Attention: You must use an Oracle database to run Netcool/Precision TN in this failover
!configuration.
Implementation overview
The failover process in this configuration comprises the following phases:
1.Startup. The first instance of Netcool/Precision TN started becomes the primary server. This server performs the typical startup procedures, including any security mechanisms, binding to the RMI registry, and creating and loading the Netcool Management Framework. The second instance of Netcool/Precision TN to start becomes the secondary server. It reads the
<netcool_install_dir>/etc/precisiontn/secondary.xml file, performs the necessary startup functionality, and then goes into a quiescent or resting state. Startup functionality for the secondary server is minimal.
2.Normal Operation. The primary server operates with no modification; the secondary server uses a combination of a semaphore and a heartbeat mechanism to detect when the primary goes down and when the primary's network or database connections are dropped. When any of these events occurs, the secondary detects it and performs a switchover.
3.Switchover. During switchover:
–The secondary server unloads or destroys all of the extensions associated with the secondary.xml file. The class definitions are also unloaded.
–The secondary server loads the extension assembly instructions specified in the
<netcool_install_dir>/etc/precisiontn/precisiontn.xml file. This means loading all the primary server extensions and their properties.
52 Netcool/Precision for Transmission Networks 5.5 Administration Guide
