Test various combinations with mac and mtu options:
- -s X:Y,virtio-net,tap,mtu=X,mac=XXXXXX
- -s X:Y,virtio-net,valeN:M,mtu=X,mac=XXXXXX
- -s X:Y,e1000,tap,mtu=X,mac=XXXXXX
- -s X:Y,e1000,valeN:M,mtu=X,mac=XXXXXX
And without options:
- -s X:Y,virtio-net,tap
- -s X:Y,virtio-net
- -s X:Y,e1000,tap
- -s X:Y,e1000