IBM 5.5 ユーザーズマニュアル

Figure 17 shows an overview of the network in this configuration: 

You must use an Oracle database to run Netcool/Precision TN in this failover 

configuration. 

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.