We have worked for a couple of weeks on installing Oracle e-Business Suit R12 (12.1.3) on Oracle 11g R2 (126.96.36.199) 2-node RAC database. The architecture consisted of two-node application layer running on Oracle Linux 5.6 and two-node RAC database.
We faced issues on configuring the APPS tier to use the SCAN IP address of the RAC database. Eventually Oracle Support suggested us to use VIP IP address instead. It worked just fine, but it was a bit disappointing to see it not working with SCAN.
We also had to give some more space in some tablespaces. We also had to do some steps to move the archived log files to the shared ASM disk.