Bridged Adapter not working version 5.2.22

[Ken The Eskimo]

Using Bridged Adapters with Windows 10 Host and Windows 10 Guest fails to work as expected. The host and the guest can not ping each other , neither can the guest ping anything outside of its own machine.

This issue I have narrowed down to having a locally administered MAC address with in the Guest machine. While the work around is to use the VirtualBox setting as the MAC address - this is not the preferred method for portability of the Disk Image File. I had narrowed it down by swapping the bound network interface lan and wifi to network 1 and network 2 and then reversing that - disabling the first network with in the guest (which had the locally administered address) - everything then worked - and I only realized it was the MAC address being locally administered within the guest - because I needed to set it for Network2 at which point everything failed to communicate again. I then administered the local mac in the Vbox Settings network page. I would prefer this to be with in the image itself in network properties. If I have several images with the same locally administered MAC , I would think the VBox Bridge would act as the router hop so that I could have multiple of this image on the same network.

[Socratis]

Related discussion in the forums: ​https://forums.virtualbox.org/viewtopic.php?f=6&t=90650

[Valery Ushakov]

Sorry, I've lost track of what was reversed to what not even half-way into the description. I understand that this is all pretty obvious for you because you've been juggling these configurations while debugging this problem for some time, but we need more details.

Please can you clearly describe each step. Who are network 1 and network 2 (are they distant cousins)? What is bridged where? Do you use several MAC addresses on one guest interface at the same time (like Solaris VNIC or Linux macvlan)? Etc, etc...

[Ken The Eskimo]

Replying to vushakov:

Sorry, I've lost track of what was reversed to what not even half-way into the description. I understand that this is all pretty obvious for you because you've been juggling these configurations while debugging this problem for some time, but we need more details.

Please can you clearly describe each step. Who are network 1 and network 2 (are they distant cousins)? What is bridged where? Do you use several MAC addresses on one guest interface at the same time (like Solaris VNIC or Linux macvlan)? Etc, etc...

[There are details in the associated forum report related discussion - however I will bullet point here - Network NICs are both set with 192.168.1.n , Class B (I also used Class C)]:

1. Laptop has Ethernet NIC wired RJ45 and WIFI.
2. Network 1 - Bridged to Ethernet NIC.
3. Network 2 - Bridged to WIFI.
4. In the 'GUEST OS' for Network 1 Adapter : WIN10 > Network Properties > Ethernet NIC 1 > Configure > Advanced > Locally Administered Address - set the MAC Address.

At this point you can not ping the host, and the host can not ping the guest.

So I shutdown the GUEST: In virtual box settings : Change the Assignment of what adapter is bridged by which network: Networking >

1. Assign Network 1 to BRIDGE the WIFI, (was bridged to the LAN adapter)
2. Assign Network 2 to Bridge the LAN-RJ45 wired NIC.(was bridged to the WIFI)
3. Restart the GUEST.
4. In the Guest OS WIN10 > Network Properties > Ethernet NIC 1(Network 1) > Disable.

At this point I was able to ping the Host and the Host was able to ping the Guest - all worked as expected.

As an FYI: My Dell precision 7720 laptop (Physical machine) in the NIC properties for the LAN card - there is no setting for locally administered MAC address. While this should not matter but it is better you have that info.

This bug condition I was able to duplicate on other laptops that were different models and did have the ability to locally administer the MAC address on the Physical NIC.

The Host and the Guest are Windows 10 Professional 64 bit. They only allow for a single MAC Address in the NIC card settings. I am using one MAC address locally administered in the GUEST OS for one Network only. The other is purely managed by Virtual Box.

If I instead administer my MAC address in the VirtualBox settings dialog and leave the GUEST OS Configure > Advanced > Locally Administered Address as NOT Present [BLANK] - then Virtual Box will assign the MAC address and this does allow the GUEST OS to work properly - but from the standpoint of it being virtual - I should be able to administer that MAC address in the Image.

[Valery Ushakov]

You are changing too many variables in your second attempt. What happens if after the first step, when you couldn't ping the host, you reboot the guest with Locally Administered Address set on NIC1, still bridged to the Ethernet?

[Ken The Eskimo]

@vushakov see below

[Ken The Eskimo]

@vushakov

"What happens if after the first step, when you couldn't ping the host ; Reboot the guest with Locally Administered Address set on NIC1, still bridged to the Ethernet?"

In the resolution section : where I changed which network was mapped to which host device. No matter how I set it up - if I have a Locally Administered MAC address - my ping host to guest and guest to host does not work EXCEPT if I setup NAT .. in which case it seems to allow host to guest and guest to host pings.

Rebooting guest , rebooting host after these things does not change the result - no ping.

If my Ethernet has locally administered MAC with in the guest - I can not ping host<>guest. No matter if it is the first Network, Second etc..

For now I am working around it - although I don't like to do this as it defeats the purpose of a single image that can be ported where needed - I now need to include the configuration files with the image.

There can still be quirks of connectivity issues when changing the IP-Address but rebooting seems to solve those. I need to change the VM IP Address as the software in the VM is used as a toolkit to connect to various on premise customer systems where they define what their systems IP Address scheme is.

[dBW]

Bridged mode decidedly broken on my VirtualBox instances, as well. Has worked over many updates until 4.2.22, same on 4.2.24, 6.0.2.

The symptoms are even stranger on Win10 10.0.17124 64-bit host, across xubuntu 16.04 and 14.04 clients:

• host: Network appears unaffected, ssh, http, https working
• client: ping works to any address
• client: Firefox browser is able to hit sites
• client: ssh hangs, eventually has Connection Timeout
• client: apt-get update (http) hangs, eventually has Connection Timeout

AsusTek box with Intel i7-4770 @ 3.4 GHz 1st Realtek onboard PCIe NIC 2nd Realtek NIC in PCIe slot

WORKAROUND: Set both NICs to NAT mode