Network connectivity between two AWS EC2 instances

Introduction

This article explains the process to establish network connection (intranode communication a.k.a network communication) between two AWS EC2 instances if both belong to the same EC2 security group.

 Using private ip addresses

Login to AWS console and choose EC2 Service.

Just put the security group name itself in the “Allow” ALL TRAFFIC with source as the security group name in the common security group.

Using public ip addresses

Add two more rows like the above shown for private ip addresses, but this time with the source as the public IP (one row for each public IP address). Do not forget to end the public ip address with /32.

adop prepare phase fails with TNS-12542 TNS-12560 TNS-00512 Address already in use

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

adop -status  (Shows that it failed at the prepare or apply phase)

 

Set the RUN file system

 
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

Oracle EBS online patching abort after adop prepare phase

If your Oracle E-Business Suite (Oracle EBS) online patching process failed only at the adop phase=prepare phase, then you can abort the online patching process by running the following commands.

 

adop -status (Shows that it failed at the prepare or apply phase)

 

Set the RUN file system

 
echo $FILE_EDITION (Must show run)

 
adop phase=abort

adop phase=cleanup cleanup_mode=full

The additional adop phase=fs_clone is required only if it failed at the actual patch apply phase i.e adop phase=apply. Otherwise fs_clone is not required.

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