ORA-03113: end-of-file on communication channel (DBD: login failed)
I upgraded my Oracle from 8i to 9i after which I have had problems in my web reporting. I use perl-cgi scripts to display the data from the DB in HTML format and excel format. After the upgrade the excel report refuses to load. The error message displayed when trying to run the production web report was:
DATABASE ERROR: Could not Connect to database: ORA-03113: end-of-file on communi
cation channel (DBD: login failed)
This then logs an error in the production database alert log -- so clearly it's finding the database just fine.
The alert log error is:
ORA-00600: internal error code, arguments: , , , , , , , 
The web reports are connecting to the production database just fine -- it's just the Excel functionality and what it executes behind the scenes that is in question.
Another funny part is the new 9i database accepts the dbi request from the test webserver, just not the production webserver for some reason.