There are two options that you can use to modify the built-in server.xml file in App Service built-in Java Tomcat docker image.
Completely overwrite the built-in server.xml file with you own server.xml. This method is simple and straightforward. But if App Service platform upgrades in the future, there will be potential risks that your own server.xml may encounter compatibility issue with our platform.
Use xsl transform to modify the built-in server.xml with necessary and minimum changes. This method is a little bit complex, but it can minimize the potential compatibility issue during App Service platform upgrades.
Completely overwrite the built-in server.xml file with you own server.xml