Did your adop phase=prepare fail in Oracle E-Business Suite 12.2.x version with the following error messages ?
Error listening on: (ADDRESS=(PROTOCOL=TCP)(Host=application-server)(Port=xxyy))
TNS-12542: TNS:address already in use
TNS-12560: TNS:protocol adapter error
TNS-00512: Address already in use
Linux Error: 98: Address already in use
Solution
Under usual circumstances, this should not be an issue at all because the Oracle EBS apps listener should be up and running all the time (The tnslsnr process) and adop phase=prepare should successfully get completed by noting that the LISTENER listener-name has already been started.
However, due to some unexplained reasons, the prepare phase may still fail. It may be an Oracle bug. But we can simply abort the online patching, do a full cleanup, stop the apps listener and retry the adop phase=prepare.
Abort and do a full cleanup
echo $FILE_EDITION (Must show run)
adop phase=abort
adop phase=cleanup cleanup_mode=full
Stop the LISTENER process
netstat -nlp | grep xxyy (Replace xxyy with the actual port number reported in the error message)
ps -ef | grep tnslsnr
Make sure the process id matches with that of the id shown from the output of netstat command above.
Now terminate the process id using the kill -15 processid command.
Wait for a minute. If it is still running, then terminate using the kill -9 processid command.
Retry
adop phase=prepare
Conclusion
This issue can be an Oracle bug. If this error occurs frequently with the adop phase=prepare, then create a service request with Oracle support at https://support.oracle.com