On Mon, Oct 31, 2022 at 04:32:27PM +0200, Edward Haas wrote:
Hi Igor and Laine,
I would like to revive a 2 years old discussion [1] about consistent network interfaces in the guest.
That discussion mentioned that a guest PCI address may change in two cases: - The PCI topology changes. - The machine type changes.
Usually, the machine type is not expected to change, especially if one wants to allow migrations between nodes. I would hope to argue this should not be problematic in practice, because guest images would be made per a specific machine type.
Regarding the PCI topology, I am not sure I understand what changes need to occur to the domxml for a defined guest PCI address to change. The only think that I can think of is a scenario where hotplug/unplug is used, but even then I would expect existing devices to preserve their PCI address and the plug/unplug device to have a reserved address managed by the one acting on it (the management system).
Could you please help clarify in which scenarios the PCI topology can cause a mess to the naming of interfaces in the guest?
Are there any plans to add the acpi_index support?
This was implemented a year & a half ago https://libvirt.org/formatdomain.html#network-interfaces though due to QEMU limitations this only works for the old i440fx chipset, not Q35 yet. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|