I've been struggling with this in Log4J, and am wondering if it's possible in Logback. If I have tomcat, with several web applications, can I have one instance of the logback jars in Tomcat/lib, and one configuration file, but distinguish between applications via variable substitution and the pattern? We are logging to SYSLOG, so I would like the pattern to include the application name. I looked through the manual, and see you can use variable substitution for specifying different files, but does substitution work in the pattern field? Can the ContextJNDISelector use a configuration file outside of the war? Ideally I would have the logging configuration file in tomcat/conf or somewhere, and have all applications use the same one. Thanks for any help!