Re: [libvirt-users] /etc/machine-id
On Saturday, June 21, 2014 5:37 PM, Gene Czarcinski <gczarcinski(a)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....