In today's post I'll cover on Unified APPL_TOP in Oracle Applications R12 which is different from separateAPPL_TOP in Oracle Applications 11i. Unified APPL_TOP make more sense if you are using multi node Oracle Applications R12.
In Oracle Applications 11i , in multi node installation each APPL_TOP have its different name and files in each APPL_TOP will depend on type of Node (i.e. Forms Node will have fmx or forms related files where as APPL_TOP belonging to CM only node will have rdf or files required to run CM node)
Starting from R12, it will use Unified APPL_TOP which means all files required for all middle tier services are included in all nodes of Multi Node installation (irrespective of services running on that node)
What are few changes because of Unified APPL_TOP ?
-- During Cloning of multi node Oracle Application install, only one copy (any one appl_top) of Application Node files need to copied to target instance. -- During Cloning of Multi Node to Single Node you don't have to merge APPL_TOP's in R12 as required in 11i . --Services start/stop If you are using adstrtall.sh to start services on a node then it will start services which were configured to start during install on that node (You can still start a specific service even though it was not suppose to configure/start by calling startup script of that specific services). To explain this better, lets assume you installed multi node R12 instance with Node 1 as Forms & Web Server where as Node 2 was installed with Concurrent Manager. Now on Node1 when you use adstrtall.sh script to start services as expected it will start Forms and Web services but unlike 11i, You can still start Concurrent Manager on Node1 by running adcmctl.sh --FND_NODES From R12 all nodes will have Y against all services (For multi Node) in FND_NODES table.
More on R12 with upgrade overview and other new features coming soon....