See also: /proc/sys/kernel/random/boot_id /proc/sys/kernel/random/uuid ---- Because the machine-id is intended to be something that persists between

See also: /proc/sys/kernel/random/boot_id /proc/sys/kernel/random/uuid ---- Because the machine-id is intended to be something that persists between reboots, it is necessarily something that would live in the filesystem, independent of the kernel. Your described functionality could be accomplished with a FUSE filesystem, though. However, that functionality would be problematic. Programs (like D-Bus) expect to be able to use it to identify whether 2 communicating processes are on the same host. If it served different bullshit to each process, it would be entirely non-functional. (Sans returning the true ID to root, this is /proc/sys/kernel/random/uuid) Perhaps instead, use a determined-at-boot value (as the machine-id(5) docs say is acceptable for stateless systems). If this is a kernel construct that isn't associated with a specific (PID?) namespace, then this would also be problematic, as different containers would be considered to be the same "host". (Sans returning the true ID to root, this is /proc/sys/kernel/random/boot_id)