Our app runs on a Weblogic server (WLS) and talks to another WLS-hosted app via a SOAP-Webservice.
When the other app was patched to a new version, some WS-requests failed indicating that the webservice in the other app wanted to JNDI-lookup the previous version of something.
After we restarted our app everything worked fine. But still you don’t want to restart a client when the server was upgraded. Moreover, a spring boot based client did not have these problems.
It turned out that WLS uses a feature called “Context Propagation” that inserts an additional SOAP-Header into the request as well as the response. This header contains a serialized object. It indicated that our app transmits the version of the other app and apperantly the other app somehow uses that information in the JNDI lookup.
How does our app knows about the version number of the other app? Probably because the other apps sends that info in the response. This explains why it worked after we restarted our app: at first it hadn’t that information at all and when it got it, it was about the new version.
What I still can’t explain is that some request were successful before the restart.
The solution is to disable “context propagation” by using a system parameter: