On Saturday, June 21, 2014 5:37 PM, Gene Czarcinski <gczarcinski@gmail.com> wrote:
I was under the impression that the value of /etc/machine-id was unqiue for every OS installation on a system. This seems to be the case on real hardware. That is, if I install Fedora 19, Fedora 20, and Fedora-rawhide on a system, they will each have a different value for /etc/machine-id.
This does not seem to be the case for qemy-kvm-libvirt virtual systems. SOmetimes they are different but I just noticed that a virtual system with both Fedora 20 and Fedora rawhide installed (btrfs partitioning), the two installations have the same value in /etc/machine-id. The two installs have different ext4 partitions for /boot, different subvols for the respective rootfs and the same/shared subvol for /home.
Maybe this snippet from the systemd-machine-id-setup(1) man page [1] explains it:
If run inside a KVM virtual machine and a UUID is passed via the -uuid option, this UUID is used to initialize the machine ID instead of a randomly generated one. The caller must ensure that the UUID passed is sufficiently unique and is different for every booted instanced of the VM.
Cheers, Cristian Ciupitu [1]: http://www.freedesktop.org/software/systemd/man/systemd-machine-id-setup.htm...