TAF does not work with Oracle EBS suite due to Forms/TAF limitations, but we can use the tns failover clause. On instance failure, when the user logs back into the system, their session will be directed to a surviving instance, and the user will be taken to the navigator tab. Their committed work will be available; any uncommitted work must be re-started.
Oracle recommends you configure the forms error URL to identify a fallback middle tier server for Forms processes, if no router is available to accomplish switching across servers.
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