Systemd Starts Killing Your Background Processes By Default (blog.fefe.de)

New submitter nautsch writes: systemd changed a default value in logind.conf to "yes", which will kill all your processes, when you log out... There is already a bug-report over at debian: Debian bug tracker.
The new change means "user sessions will be properly cleaned up after," according to the changelog, "but additional steps are necessary to allow intentionally long-running processes to survive logout. To effectively allow users to run long-term tasks even if they are logged out, lingering must be enabled for them."