One of our clients has moved to Siebel 8.1.x and is considering migrating their Haley Rules in previous version to OPA.
Is there a documentation to help with Haley to OPA Migration path.
Is there a upgrade tool which can automate the migration, or rules need to be reimplemented in OPA?
Sorry, but no such documentation exists because there are not automated tools nor standard upgrade steps to follow and the upgrade process depends heavily on how the Haley rules were written (e.g. which features and capabilities were leveraged) and to what extent the original implementation stayed within the boundaries of "supported" approaches, features and functions of the Siebel integration.
There are consultants with experience in both products - engaging with them to lead the effort to analyze the existing solution and design appropriate approaches in OPA, at a minimum, would be the recommended approach.