Hi Mathew, I would suggest start with latest Tomcat 10.x version currently 10.1.50
Unfortunately I don't have experience with IBM operating systems, but I could confirm it works very reliably in one of our projects using Linux kernel and x64 Temurin JVM version 25.0.1. This jvm is available for s390x systems too. https://adoptium.net/temurin/releases/?version=25 You don't write what is your current Tomcat version so I assume it is Tomcat 9.x or older. The upgrade may need more changes in web application because of JakartaEE is not compatible to JavaEE because of some package name changes from javax to jakarta See e.g. here https://www.jetbrains.com/guide/java/tutorials/migrating-javax-jakarta/use-migration-tool/ Regards, Zdenek Henek On Tue, Jan 20, 2026 at 9:55 AM MATHEW THOMAS via users < [email protected]> wrote: > Hi, > > We are currently running Tomcat 10.1.13 on z/OS 3.2. We plan to upgrade to > z17 and z/OS 3.2, can you advice on any know requirements or fixes needed > for this and confirm if there are any compatibility issues? > > Kind regards, > > > > Mathew Thomas - Systems Engineer >
