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Forms Socket/Servlet

Following are the queries answered by me in one of the forums.

1. Will it be possible that the forms tier load also will be balanced by Hardware load balancer ? Before we know the answer for this question, i guess its better to know the forms architecture. Forms in Oracle Applications can be configured in 2 modes.

a. Socket Mode and
b. Servlet Mode.

a. Socket Mode: By default forms 6i comes with Socket Mode install. If customer hasn't done any changes then he would still be using Socket Mode. In socket mode then forms cannot be loadbalanced using hardware load balancer. In this case you need to use Forms Metric Server Load Balancing.

For configuration details refer to document: 217368.1 Section 2.4. Forms Server / Metrics Layer Load Balancing.
Forms socket mode connections are always faster compared to servlet mode(if hardware resources are infinite then this should be of little concern). This is the only reason why customers use forms socket mode else Servlet mode is better.

b. Servlet Mode: It is easy to configure forms servlet by changing few parameters in the context file and running autoconfig. This architecture converts all forms requests to be handled as http requests. So once Hardware Loadbalancer is configured with Oracle Applications then there is no special configuration required to handle forms tier load.

For configuration details refer 201340.1 Using Forms Listener Servlet with Oracle Applications 11i

Following are the advantages:
* Support for a broader range of firewalls and proxies
* No protocol restriction (HTTP/1.1 or HTTP1.0)
* No extra process to manage (No Forms listener process)
* No specific certificate to purchase/manage for SSL deployment (Done at the web server level)
* Standard Load balancing techniques support
* Internet Explorer 5.0 native support in intranet and internet deployment2.

In case of failure of DB node the standby should be activated using the IP of production server or app tier will require some change?It depends on how DB failover is achieved.

a. If you are assigning the IP address of failed Production server to a new server and also the hostname then there is no change required on apps tier. (Recommended)
b. If you are assigning only the IP not the hostname then you must change the hostname of the db server in the context file and run autoconfig on all the apps tiers.

Hope this helps.



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