I am experiencing the following communication problem with my VM server running on server 2012 hyper-v host:
when a network package leaves the vNIC of the VM it has the source mac address of the vNIC however when the same package leaves the physical NIC of the Host the package no longer has the source MAC address of the vNIC but that of the physical NIC.
It forgot to mention that the uplink of the virtual switch on the host is a network team using LACP and that uses the source and destination IP address as its load balancing mechanism.
Please note the following:
- this behavior disappear when I either remove one of the cables from one of the teamed nics (the sources MAC is always that of the vNIC when the packet leaves the host etc)
- the problem also disappears if I configure a static ARP in the client
- The above behavior does not apply for all communication for example I can have the cables of both teamed NICS connected and simple change the IP of the above problematic TFTP client form 192.168.1.22 to 192.168.1.13 and the communication works OK as the source MAC address of the VM will always be the correct MAC address that belongs to the vNIC.
Last but not least we have tried, replacing the NICS in the server, connecting the host server to a different switch and even replacing all the cabling to the host server but none of these helped to resolve the problem.
Has anyone seen this behavior? Any idea what could be causing this?
Regards,
Screech