[systemd-devel] on the default for PredictableNetworkInterfaceNames

[Greg KH]

On Mon, Apr 11, 2016 at 11:56:00AM +0200, Xen wrote:
> The predictability issue seems to be due to using a MAC address.
> 
> AFAIK a reinstall will not change PCI bus devices etc.

No, PCI device numbers change all the time, they are not guaranteed to
be stable at all.  Yes, lots of machines do not have them change, but a
non-small number do.  Most of the time they change only if you have
changed a PCI device (which includes thunderbolt and docking stations,
quite common these days), or when you update your BIOS, but my favorite
machine would renumber the whole bus every other boot for no good reason
at all.

So don't think of PCI bus numbers as static, they aren't, sorry.

greg k-h