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Re: Guest bridged adapter using Host MAC Address

PostPosted: 21. Nov 2012, 02:36
by rusl
I'm also having the exact same issue and wondering if anyone came up with any solution? Trying to run Ubuntu 12.04 guest inside of OSX 10.7

Thanks

Re: Guest bridged adapter using Host MAC Address

PostPosted: 20. Nov 2014, 11:43
by Adam_M
I'm having the same problem.
My router sees traffic from my VM with Host mac...
Was this ever resolved?

VM is bridged on hosts WIFI
Promiscuous mode is denied

Re: Guest bridged adapter using Host MAC Address

PostPosted: 17. Dec 2014, 06:21
by delitescere
Ditto :(

Re: Guest bridged adapter using Host MAC Address

PostPosted: 7. Feb 2016, 03:30
by riramar
Found the answer.

https://www.virtualbox.org/manual/ch06. ... rk_bridged
Note
Bridging to a wireless interface is done differently from bridging to a wired interface, because most wireless adapters do not support promiscuous mode. All traffic has to use the MAC address of the host's wireless adapter, and therefore VirtualBox needs to replace the source MAC address in the Ethernet header of an outgoing packet to make sure the reply will be sent to the host interface. When VirtualBox sees an incoming packet with a destination IP address that belongs to one of the virtual machine adapters it replaces the destination MAC address in the Ethernet header with the VM adapter's MAC address and passes it on. VirtualBox examines ARP and DHCP packets in order to learn the IP addresses of virtual machines.

Thanks!
Ricardo

Re: Guest bridged adapter using Host MAC Address

PostPosted: 2. Apr 2019, 22:57
by bogoid
I realize this is a very old thread. But it seemed a good match to my problem.

Host: MacBook Pro, macOS 10.14.3, VirtualBox 6.0.4 r128413 (Qt5.6.3, mac address 3c:15:c2:dc:6f:02, ip 192.168.192.76 (from dhcp reservation)
VM: Win7, Bridged Adapter, en0: Wi-Fi (AirPort), Intel PRO/1000 MT Server (82545EM), Promiscuous deny, mac address 08:00:27:18:2d:fd, ip 192.168.192.80 (from dhcp reservation)

When from another machine on the subnet I ping or ssh the VM, arp tells me that the VM is using the host mac address.
192.168.192.76 ether 3c:15:c2:dc:6f:02 C enp2s0
192.168.192.80 ether 3c:15:c2:dc:6f:02 C enp2s0

Similar setup with another Mac, but using cat5, it gets the VM's mac address, as does when it's a Linux host on cat5.

If I use arp on this other machine to force the VM's IP to map to the VM's mac address, there is no reply.

This is mostly harmless, EXCEPT...

Google WiFi won't port forward. I'm guessing that it's because its port forward mechanism synthesizes packets with the VM's mac address and the VM's ip. I don't know what Google WiFi does to figure out the VM's mac address.

Re: Guest bridged adapter using Host MAC Address

PostPosted: 2. Apr 2019, 23:46
by socratis
I'm sorry, but why doesn't the quoted passage from the User Manual, on the post right above yours, cover your situation?

bogoid wrote:Google WiFi won't port forward. I'm guessing that it's because its port forward mechanism synthesizes packets with the VM's mac address and the VM's ip. I don't know what Google WiFi does to figure out the VM's mac address.

Are we talking about this https://store.google.com/us/product/google_wifi? Yeah, I don't know either what that thing does or how it does it. And why should we? There are a gazillion of routers out there, and not all are the same. Some combinations of Routers/Access Points, WLAN cards and drivers work, some don't. See: Bridging & Wifi - Supported hardware and add your experience.

I still haven't figured out how this affects you in RealLifeā„¢, could you explain the issue at hand a little bit?