I was recently trying to fix one error and after installing patch 31 on IBM websphere 18.104.22.168, I came across a weird problem – My application was trying to connect to database using DBCP common pool and it suddenly stopped working after applying patch. The error message logged in file was “Network adapter could not establish connection”.
It was quite unexpected to see this error as I could easily able to connect database from other machine. So I thought of writing simple JDBC code and tried to connect to the database from Websphere machine. To my surprise, this code was working as expected and could able to connect the database. It was quite frustrating as we couldn’t able to figure out why DBCP pool stopped working after installing patch 31. After googling on this problem, I found that using ojdcb5.jar would reveal more details about error and it worked for me. This time, rather than just saying “Network adapter…”, it also logged an error message as “Address already in use : NET_Bind”. Well this was obviously more confusing than the earlier one, as it wasn’t quite clear what was the cause of the error. The error continued to show up after restarting Websphere and even after restarting whole machine.
After reading patch 31 readme notes, I found that it is also necessary to update IBM JVM fix compatible for patch 31. The JVM patch is not bundled with Websphere patch and should be applied separately.
Yippee, after installing the JVM patch the “Address Already in use…” error got whooshh… Hence I would like to advice Websphere users to carefully go through the readme notes of any patch and make sure that dependent patches are applied correctly OR else you might get caught in trap of errors.