Also what is the best way to remote launch a B4J non-ui app on a server from another machine?
If you have a Windows OS on your servers: I have been using a simple utility call "Restart On Crash" for this purpose for a good many years on several systems (including on AWS EC2 instances and headless/legless mini PCs in remote locations) and it never falters.
It can be configured to automatically launch when Windows is started and will then launch (and monitor) any apps you have told it about.
It is very easy to use (install and tailor in minutes) and even has a flat file log which I monitor with a B4J app that SMSs me if anything falls over.
Just google "restart on crash" it is readily available - FREE.
Highly recommended...