[logback-user] Hostname or process ID in log messages

Hi, I am wondering if Logback has a solution to identify the process or the host that is running the application. This would be relevant for applications with instances running in parallel, but writing their log to a central repository (eg using DBAppender to a common database). A typical scenario would be load balancing a web application in the cloud, or a heavy computation split over several processors. If an instance fails, I would be important to have the log message to distinguish this instance among others. I think that MDC could do this job. However, this would work only for threads that are under my control. Is it possible to add some log meta-data globally to the logger context? Best regards, Daniel Felix Ferber