Dual connected networks on Win10 host breaks host-only network adapter

Discussions related to using VirtualBox on Windows hosts.
Post Reply
henrikv
Posts: 6
Joined: 16. May 2017, 08:34

Dual connected networks on Win10 host breaks host-only network adapter

Post by henrikv »

Hi VMforum,

Host:
  • Microsoft Windows 10 Enterprise
    v.10.0.15063 Build 15063
    Antivirus: Corporate controlled Windows Defender
    User rights: Administrator, with a few exceptions (but I can access and/or change most)
    Physical network cards:
    • Gigabit LAN
      Dual-band AC WiFi
Guest:
  • Microsoft Windows 7 Professional
    v.6.1.7601 Service Pack 1 Build 7601
    Antivirus: Standard
    User rights: Administrator
    Configured network adapters:
    • Adapter 1:
      • Attached to: Bridget Adapter
        Name: Brigded to one of the above physical network (changed depending on requirements)
        Adapter Type: Intel PRO/1000 MT Desktop (82540EM)
        Promiscous Mode: Deny
      Adapter 2:
      • Attached to: Host-only Adapter
        Name: VirtualBox Host-Only Ethernet Adapter
        Adapter Type: Intel PRO/1000 MT Desktop (82540EM)
        Promiscous Mode: Deny
VirtualBox:
  • 5.1.22 r115126 (Qt5.6.2)
    Preferences -> Network -> Host-only Networks -> VirtualBox Host-Only Ethernet Adapter:
    • IPv4 Address: 192.168.56.1
      IPv4 Network Mask: 255.255.255.0
      DHCP Server:
      • Server Address: 192.168.56.100
        Server Mask: 255.255.255.0
        Lower Address Bound: 192.168.56.101
        Upper Address Bound: 192.168.56.254

INFO: During below examples, it makes no difference whether the virtual network adapter 1 for the guest is connected the the physical LAN or WIFI adapter.


Example 1
  • Host gigabit LAN adapter connected to DHCP enabled network
    Host dual-band AC WiFi adapter disconnected (either not connected to a WiFi, or disabled under "Network Connections")

    Result: Guest can PING host IP: 192.168.56.1, and programs inside the host can exchange data with services on the host. Everything is working as intended.
Example 2
  • Host gigabit LAN adapter connected to DHCP enabled network
    Host dual-band AC WiFi adapter connected to WiFi (have tried with both DHCP and static IP without gateway configuration for this adapter during this example)

    Result: Guest can not PING host IP: 192.168.56.1, and programs inside the host can not exchange data with services on the host. No connection through the host-only network.
Example 3
  • Host gigabit LAN adapter disconnected (either cable physically disconnected, or disabled under "Network Connections")
    Host dual-band AC WiFi adapter connected to WiFi (have tried with both DHCP and static IP without gateway configuration for this adapter during this example)

    Result: Guest can PING host IP: 192.168.56.1, and programs inside the host can exchange data with services on the host. Everything is working as intended.

To sum up the above. When only one physical host adapter is connected to a network and/or enabled at a time (example 1 and 3), the host-only network works as intended. However, when both physical host adapters are enabled and connected to different networks at the same time (example 2), all communication via the host-only network adapter is blocked/denied. Whether or not the IP configurations are DHCP or Static (without gateway) doesn't seem to influence the result.


Communication from host to both physically connected networks is working as intended, it is only the VirtualBox host-only network that stops working.


I have been working with this problem for a while (took me some time to actually realize why it sometimes were working, and sometimes not), googling a bunch, but I am running out of ideas as to what can cause the above described problem.


If any further info is needed, kindly ask, and I will provide as best as I can :wink:


Thanks in advance
Henrik V. Nielsen
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by scottgus1 »

Only problem I can see is that it is not normal to have a standard windows OS connect to two different network paths to the same network ie both ethernet and Wi-Fi at the same time. (I am assuming that the Wi-Fi access point is connected to the same network as the ethernet port.) Server OS's like 2008 2012 2016, etc. can do that sort of thing, but not workstation OS's like 10.

This may be confusing the host network so much that it just gives up and takes Host-Only down with it.

Your reported tests reveal that Host-Only does work when either ethernet or Wi-Fi are connected but not when both are connected. Theoretically, Host-Only should be independent, but maybe there's a cross-glitch somewhere that the developers haven't noticed, or that 10 has thrown at them unexpectedly. At the risk of stating the obvious I should suggest not connecting both ethernet and Wi-Fi at the same time, since your host OS is probably not designed for that.

Why Host-Only goes down when both are connected will have to be for better heads than mine.
Martin
Volunteer
Posts: 2560
Joined: 30. May 2007, 18:05
Primary OS: Fedora other
VBox Version: PUEL
Guest OSses: XP, Win7, Win10, Linux, OS/2

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by Martin »

What are the IP address ranges used in your LAN and in your WLAN?
henrikv
Posts: 6
Joined: 16. May 2017, 08:34

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by henrikv »

To scottgus1

During the testing described, the LAN were connected to our company network (range 10.65.32.xxx), and the WiFi to a small router I have at my desk to connect test equipment (range 192.168.0.xxx). All subnets are 255.255.255.0.

So as you can see, the two networks are not the same. As a matter of fact, the small router exist exactly to separate testing from corporate net.

Also, connecting win10 to two different nets works fine on the host (I can talk to both networks as expected). It is only VirtualBox that are having problems with the host-only adapter.

The claim that host-only network adapter should be independent, would also be my expectations, but as stated, it doesn't work. Hopefully some über geek knows something, but thanks for the reply :wink:





To Martin

See above answer to scottgus1.
socratis
Site Moderator
Posts: 27330
Joined: 22. Oct 2010, 11:03
Primary OS: Mac OS X other
VBox Version: PUEL
Guest OSses: Win(*>98), Linux*, OSX>10.5
Location: Greece

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by socratis »

I was recently asked by a developer if I noticed any HostOnly weird behavior in the forums. This certainly qualifies. They were fixing some things for the HostOnly network stack for 5.1.24, so give it a shot. Fresh from the oven ;)
Do NOT send me Personal Messages (PMs) for troubleshooting, they are simply deleted.
Do NOT reply with the "QUOTE" button, please use the "POST REPLY", at the bottom of the form.
If you obfuscate any information requested, I will obfuscate my response. These are virtual UUIDs, not real ones.
henrikv
Posts: 6
Joined: 16. May 2017, 08:34

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by henrikv »

Hi socratis,

Yes, this would most certainly fit that description.

Wow, that were indeed fresh from the oven. I am damn sure I checked for new releases just before posting this problem, but only found the old 22 revision :?

Firstly I just updated VirtualBox and tested straight away, but with no change. But to ensure nothing lingered from the old setup, I performed below steps:
  • 1. Closed all VM (not just pause, as I usually would do)
    2. Removed adapter 2 (host-only) from all VMs
    3. Rebooted host OS
    4. Removed host-only adapter under VirtualBox preferences
    5. Rebooted host OS
    6. Created a new host-only under VirtualBox preferences (with same specs)
    7. Rebooted host OS
    8. Reattached adapter 2 (host-only) to all VMs
    9. Booted Vm and updated guest additions
    10. Rebooted VM
    11. Tested
I hope you will agree that it would be hard pressed to do more to ensure nothing old. Else, kindly enlighten me :wink:

But after testing, the problem still prevails. With gust running, the second i connect the second network within the host, the pings from guest to host dies. The second I disconnect the second network, the pings start coming through again.

I you are still in contact with said developer, kindly ask if he has any suggestions. If you need any further information, I will be more than happy to provide as much as possible. Just send instructions/command you with to receive the result from, and I will throw them at my system. Anything to help locate/fix this quirk :wink:

PS. If I can find the time this forthcoming weekend, I will try to create a similar setup on my home PC.
henrikv
Posts: 6
Joined: 16. May 2017, 08:34

Re: Dual connected networks on Win10 host breaks host-only network adapter

Post by henrikv »

Just to clarify. After advice from socratis, I updated to new release, and will therefore forward be running:


VirtualBox:
  • 5.1.24 r117012 (Qt5.6.2)
    Preferences -> Network -> Host-only Networks -> VirtualBox Host-Only Ethernet Adapter:
    • IPv4 Address: 192.168.56.1
      IPv4 Network Mask: 255.255.255.0
      DHCP Server:
      • Server Address: 192.168.56.100
        Server Mask: 255.255.255.0
        Lower Address Bound: 192.168.56.101
        Upper Address Bound: 192.168.56.254
Post Reply