3.11.2 Configuration in which executing node and standby node of Application Server are in 1-to-1 ratio (when using transaction service)
This subsection describes the configuration where the executing node and the standby node of Application Server are in 1-to-1 ratio and the transaction service is used.
- Organization of this subsection
(1) Features of the system configuration
This is a system configuration that uses a transaction service when using a global transaction. A shared disk device is required in such cases.
This subsection also describes the configuration where node switching is performed by Application Server. For details about the configuration where node switching is performed by Management Server, see 3.11.3 Configuration in which executing node and standby node of Management Server are in 1-to-1 ratio.
The following figure shows an example of a configuration where a transaction service is used:
|
|
![[Figure]](GRAPHICS/ZU034500.GIF)
Note: For other legend items, see 3.2 Description of the system configuration.
- Features
-
-
The executing node and standby node are configured in a 1-to-1 ratio.
-
A shared disk device is required.
-
When the database has a cluster configuration and if Application Server identifies only the virtual address (Logical address), you can still establish the connection.
-
For details about allocating Management Server and Application Server on the same machine, see 3.11.3 Configuration in which executing node and standby node of Management Server are in 1-to-1 ratio.
-
- Flow of requests
-
The client recognizes one machine for both the Application Server instance in the executing node and the instance in the standby node. All the requests are sent to Application Server in the executing node.
- Node switching flow
-
Node switching is executed when there is a failure in the Application Server machine in executing node. Node switching is executed when the OS or Administration Agent is down. Also, node switching is performed when a command is executed explicitly for node switching, or when there is an event where node switching is to be performed for cluster software.
On executing node switching, Administration Agent of Application Server in the standby node and the processes that were stopped until then, are started. Also, the information saved to the shared disk is inherited for transaction information.
(2) Processes to be invoked on the respective machines
The software and processes required on respective machines are the same as when the transaction service is not used.