The system has encountered an error when servicing the request, Please try again. If the error persists, please contact the system administrator.

While accessing R12.2 EBS url we have faced this below mentioned error

"The system has encountered an error when servicing the request, Please try again. If the error persists, please contact the system administrator."

In Weblogic Console, all the services are up and running successfully.

In Oacore_server.log file:

java.lang.NoClassDefFoundError: Could not initialize class oracle.apps.fnd.functionSecurity.User

In oacore_server.out file:

Exception in static block of jtf.cache.CacheManager. Stack trace is: oracle.apps.jtf.base.resources.FrameworkException: IAS Cache initialization failed. The Distributed Caching System failed to initialize on port: 12345. The list of hosts in the distributed caching system is: 172.16.1.1 . The port 12345 should be free on each host running the JVMs.

Solution:

Shut down the application services and check the java cache port number is still accessing or not.

$netstat -ntpl |grep 12345
(Not all processes could be identified, non-owned process info
 will not be shown, you would have to be root to see it all.)
tcp        0      0 ::ffff:172.16.1.1:12345 :::*                        LISTEN      6171/java

find the process for this port number and kill the process.

$ps -ef|grep 6171
applmgr   6171     1  0 Jul27 ?        00:51:22 /u01/applmgr/fs1/EBSapps/comn/util/jdk32/bin/java -
applmgr  27304 24214  0 16:19 pts/0    00:00:00 grep 6171

$kill -9 6171

Start the application services and this time ebs url worked fine without any issue.