I am unable to access anything outside of the host OS from a VM when subnet was changed.
Dell 2950 III, dual Xeon 2.0 12 GB Memory, 4 500GB drives.
Host OS: Win Server 2008 Standard
VM: Win Server 2003 R2 SP2 (Integrations Services Installed)
Switch 1: Cisco 3750e 48 port (192.168.15.0/24 on VLAN 10 (TEST subnet)) (192.168.13.0/24 on VLAN 2 (CORP subnet))
I started with Win 2k8, configured IP (192.168.15.202/24), installed Hyper-V Role, created new VM with Win 2k3 R2, installed integration services, configured legacy network adapter and provided IP (192.168.15.203/24).
I was able to access all resources (CORP subnet), including Internet. Downloaded and Installed SQL Server 2005 Standard, Windows Sharepoint Services 3.0 and Visual Studio Team Foundation Server. By the way, all of this was done via Remote Desktop from my home to the corporate office.
I then moved the box to a different subnet, changed the IP on host (192.168.13.202/24) and VM (192.168.13.203/24) and cannot access anything other than the host IP.
I can ping the host IP from the VM, but nothing else and can ping the VM from the host OS and everything else.
Worked through this for a few days by changing the network adapter type, disabling the firewall on host and VM and finally removed Hyper-V Role and re-installed it. Created new VM using Win 2k3 .vhd and still cannot acees anything outside of the host OS.
I tried installing a new fresh VM using Win 2k8 and 2k3 and cannot access outside resources from them as well.
Anyone have any ideas what could be wrong?
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i did try what you said previously when I was onsite yesterday. When I was working remotely via Remote Desktop and removed the virtual network, I lost connectivity. I went onsite and re-created the virutal network and I still could not access resources outside of the host. Host connectivity is fine.
The virtual network is setup as an External network and I cannot get a DHCP address to the VM NIC.
dariusg - Yes, that is correct.
mutahir- I have tried several times.
I'm beginning to think it is something in the Host OS. I have created 2 more virtual machines and cannot connect to anything outside of the host os.
I'll go onsite tomorrow and uninstall the physical nic from the host os, remove the Hyper-V role and re-install them and see what happens from there.
Yes, before uninstalling, I would say to apply any windows updates / sps and download latest nic drivers / firmware
How many Nics do you have in your server ?
If you have Two nics in your server, connect the 2nd as well to your ethernet network and then use that as virtual network type external and then see if that helps ;
Keep us posted
On the host running Hyper-V, check the LAN connections properties for the physical nic port and the virtual nic. The physical nic should only have checked "Microsoft Virtual Network Switch Protocol". The virtual nic should have nothing checked.
In addition, when I was setting up Hyper-V and configuring the LAN connections, my external nic's IPv4 settings would get it's default gateway reset whenever I would change any other setting. I would have to go in a second time and set the gateway again before it would stick. It could just be my server, but it was happened to me and tripped me up for many hours.
That's the problem then. On the virtual nic on the host OS, uncheck everything.
The rational is the physical nic port should run as a pure transparent switch port (think a "1 port switch"), so it uses Microsoft's special VNS protocol which does just that. The virtual nic is sort of a placeholder so that the VM OS's themselves can each use whatever LAN connection properties they want, therefore it needs nothing checked.
To clarify, you would set your Host OS static IP on one physical port and the other physical port would be configured with the VNS protocol enabled and nothing else. Then you would have a third LAN connection (after you run the wizard in hyper-v to create a virtual network) which represents the virtual nic to be used by all your virtual machines. This third LAN Connection is secretly bound to the physical NIC port you configured with the VNS protocol.
It's a lot to get your head around, but bottom line is one physical NIC port will only be used by the Host OS for it's normal network communication (like windows updates, etc) and it will not be used at all by your virtual machines.
I have attached the screenshots
This server is using ONE NIC and have Hyper-V
Make sure your settings are like this, basically on your actual real physical network card you would only have "virtual network switch protocol" binded and nothing else ;
On the Virtual Nic hyper-v creates, that will have the IP address and will have everything checked apart from "Virtual Network Switch Protocol"
Check your settings as per the screenshots and post back your findings.
Virtual NIC Settings in Network Sharing Centre
HV MNGR Virtual Network
Actual Physical Network Card on the Server Properties
mutahir- The screenshots you posted are exactly how my single NIC configuration is/was setup.
I have someone onsite now and have added another ethernet cable. both NIC's are set for DHCP right now and are able to obtain an IP from the DHCP Server, setup the VM's vurtual network but still am not able to get outside of the Host OS.
GREAT NEWS....I ended up uninstalling the NIC's from Device Manager, rebooted the Main Server, reconfigured everything and am now able to access all resources and the internet!!!! :) I'm happy now.
Just as I thought, it was evidently something with the NIC on the host OS.
Great stuff ;
Glad it solved
DarkJedi, yes you are right and I personally implement hyper-v with two nics or even more depending on the traffic, but the user was already pre-configured with one nic, i did advised him to use the 2nd nic though - but you are right that it should always be the case to use a seprate nic
Also, I think somehow the tcpip stack got confused in this scenario ; I think when you changed the IP addresses the change wasn't completed properly on the nic and the virtual network switch protocol - thus uninstalling the nics and adding them back in solved it :-)
Will keep this in mind for future
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by: mutahirPosted on 2009-10-31 at 07:51:20ID: 25709984
In Your Hyper V manager,
Check that the network adapter you have tied on to your hyper-v virtual network is set to type as "external"
http://blogs.msd
http://w
If none of the above works :
Remove the virtual network - unbind your network card from virtual network
Then verify you can access the physical subnet by your Hyper-V HOST system (server 2008)
Then create a virtual network bind the proper network card , select network type external
then double check your vm settings to make sure its using the right virtual network
power on your vm and you should be able to get a IP from the proper subnet and access resources.