We are upgrading our WebLogic Application Server from 6.1 to 9.2. After migrating a web service, is it correct that the client applications of the web service will also need to migrate? Does this mean that we need to provide two instances of the same web service, one running on WebLogic 9.2 and another on WebLogic 6.1 until all the client applications (developed by other departments or even companies) also go through their migration? What is the best way to handle the migration of web services?
One of the benefits of WS is that they decouple the client from the server. As long as the WS API doesn't change, it shouldn't matter which server the service is running on. It's possible to inadvertently introduce server dependencies, though, so you should check that as part of the migration testing.