Internal Server Error while accessing login page.

Question

Hi,
We have recently upgraded our database from 9.2.0.8 to 11.2.0.3 on AIX 6.1 platform (EBS version 11.5.10.2). We are not able to get the login page and receiving Internal Server Error on the login page without any error messages.
On checking we have found following errors in mod_jserv.log:
[25/10/2013 05:53:42:935] (ERROR) ajp12: Servlet Error: java.lang.NoClassDefFoundError: oracle/apps/fnd/sso/SessionMgr: oracle/apps/fnd/sso/SessionMgr
[25/10/2013 05:53:42:935] (ERROR) an error returned handling request via protocol "ajpv12"
[25/10/2013 05:53:42:935] (INFO) balance: continuing to ibmapptest:16070
[25/10/2013 05:53:42:935] (ERROR) balance: 12386336 internal servlet error in server ibmapptest:16070
[25/10/2013 05:53:42:935] (ERROR) an error returned handling request via protocol "balance"
We tried clearing the cache directories and bounced Apache but that dint help.
Why would we be receving this error and how to resolve it?

Answer 1

OK, this is an all too common issue - the logs are insufficient so you may well have to try some extra debugging to properly understand the problem.
If you have Metalink access try this: NOTE.249669.1 How To Collect Apache and Jserv Debugging
Basically, you should do the following - and maybe upload the logs here if you want to. I assume you are on 11.5.10. If not, then amend as appropriate:
Enable de-bug for Apache and Jserv:
1. Shut down the oracle application server.
2. Backup or change the name of the following files:
IAS_ORACLE_HOME/Apache/Apache/logs/error_log
IAS_ORACLE_HOME/Apache/Apache/logs/error_log_pls
IAS_ORACLE_HOME/Apache/Apache/logs/access_log
IAS_ORACLE_HOME/Apache/Jserv/logs/mod_jserv.log and jserv.log
After making a copy of these files or after renaming them, please delete
them from these directories. This enables new log files to be created
when the applications server is restarted and will help you to focus on
the current problem.
3. Enable debug logging for Apache
Update IAS_ORACLE_HOME/Apache/Apache/conf/httpd.conf to set the LogLevel parameter:
LogLevel debug
4. Enable debug logging for Jserv and mod_jserv
a) Update iAS_ORACLE_HOME/Apache/Jserv/etc/jserv.conf to set ApJServLogLevel parameter to:
ApJServLogLevel debug (from warn)
b) Update iAS_ORACLE_HOME/Apache/Jserv/etc/jserv.properties to set the
log=true
log.channel.info=true
5. Enable debugging in ssp_init.txt
Update iAS_ORACLE_HOME/Apache/Jserv/etc/ssp_init.txt to add Debug:
DebugLevel=5
DebugSwitch=ON
6. Please re-start the application server
7. Reproduce the problem
8. Upload the following files:
IAS_ORACLE_HOME/Apache/Apache/conf/apps.conf and httpd.conf
IAS_ORACLE_HOME/Apache/Apache/logs/error_log_pls
IAS_ORACLE_HOME/Apache/Apache/logs/error_log and access_log
IAS_ORACLE_HOME/Apache/Jserv/logs/mod_jserv.log and jserv.log
IAS_ORACLE_HOME/Apache/Jserv/logs/jvm (all files in this directory)
DA