[Solved] Admin Server Startup Issue in EBS (R12.2) Must Run On Primary Node
Are you facing the 
annoying “adadminsrvctl.sh should be run only from the primary node <hostname>” error while starting the Admin Server in Oracle E-Business Suite (R12.2)?
So, the blog post at www.k21academy.com/appsdba57 is what will 
cheer you up.
The blog post explains:
❖ What is the Admin Server & Context File?
❖ The Root Cause of the Error
❖ The fastest 
Fix for the Error