Re: macvtap direct
On 5/13/20 12:52 AM, Subhendu Ghosh wrote:
Hi
Couple of questions around macvtap direct usage:
1) is the document here current?
https://libvirt.org/formatnetwork.html#examplesDirect
Yes. None of that has changed in any major way in many years.
I have been able to get host to guest network traffic without any
special configuration or switch since Fedora 28 when I first started
using it. Using <forward mode=vepa> requires switch port mirroring, but
just using <forward mode=bridge> doesn't.
If that is the case, then either your guest and host have a secondary
network connection, or your switch is mirroring traffic and you just
didn't know about it. The inability to do direct host<->guest
communication is inherent in the design of macvtap interfaces.
2) do any of the language libraries make assumptions that libvirt
networks must have a <bridge name=xx> attribute? Foreman's Ruby
interface to libvirt errors out with attempting to build a VM on a KVM
host with a network defined with <forward mode=bridge>
https://projects.theforeman.org/issues/25890
The 2nd line in the log attached to that issue report says this:
Call to virNetworkGetBridgeName failed: internal error: network
'macvtap-net' does not have a bridge name.
So, your application (or whatever this "Foreman's Ruby interface to
libvirt" is) has called virNetworkGetBridgeName() (whatever it's called
in the Ruby bindings), and since you have a macvtap network, which has
no bridge device, libvirt sent back an error. You need to find whatever
in your code is calling virNetworkGetBridgeName().