Log file location for Oracle E-Business Suite R12

Below list of  log file locations could be helpful for your issue:

- Apache, OC4J and OPMN:

$LOG_HOME/ora/10.1.3/Apache
$LOG_HOME/ora/10.1.3/j2ee
$LOG_HOME/ora/10.1.3/opmn

- Startup/Shutdown Log files:

$INST_TOP/logs/appl/admin/log

- Patch log:

$APPL_TOP/admin/$SID/log/

- Autoconfig log file:

Apps:

$INST_TOP/apps/$CONTEXT_NAME/admin/log/$MMDDHHMM/adconfig.log

Db:

$ORACLE_HOME/appsutil/log/$CONTEXT_NAME//adconfig.log
$ORACLE_HOME/appsutil/log/$CONTEXT_NAME//NetServiceHandler.log

- Concurrent log:

$INST_TOP/apps/$CONTEXT_NAME/logs/appl/conc/log

- Clone log:

Preclone log files in source instance

Apps:

$INST_TOP/apps/$CONTEXT_NAME/admin/log/ (StageAppsTier_MMDDHHMM.log)

Db:

$ORACLE_HOME/appsutil/log/$CONTEXT_NAME/(StageDBTier_MMDDHHMM.log)

Clone log files in target instance

Apps :

$INST_TOP/apps/$CONTEXT_NAME/admin/log/ApplyAppsTier_.log

Db:

$ORACLE_HOME/appsutil/log/$CONTEXT_NAME/ApplyDBTier_.log

- Alert Log File:
$ORACLE_HOME/admin/$CONTEXT_NAME/bdump/alert_$SID.log

Reference:

How to find location of Install, Autoconfig, Patching , Clone and other logs in R12 [ID 804603.1]

Oracle Application Server Diagnostic Tools and Log Files in Applications Release 12 [ID 454178.1]

Oracle Applications System Administrator’s Guide

source:http://heliosguneserol.wordpress.com/2010/04/13/log-file-location-for-oracle-e-business-suite-r12/