Hyper-V VM's cannot access the internet.

hi all,

we have a setup consisting of:

1. physical instance of server 2008 SP3 R1 not part of a domain- running hyper-v with 5 Nics. 4 of them are in a balancing team which is assigned as an external network within hyper-v and the other one is the servers own NIC for remote admin.

2. Virtual instance of SBS2008 which is domain controller, exchange, DHCP, DNS server etc.

the issue is this... the SBS is unable to connect to the internet. i have no idea why but it can access and ping the internal network.. it says that it has internet connectivity but you cannot reach the internet or ping any external addresses. it did work on setup at the weekend but has dropped today.

why would this happen?

on the physical server in the network and sharing centre it states that the connection only has local connectivity so i assume the issue is there but why could this happen? could it be a issue with the way the nics are setup?
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Svet PaperovIT ManagerCommented:
The teamed NICs are not officially supported by Microsoft but it doesn’t matter if it works. I am using teaming as many guys out there and I do not have any problems with that.

Since you are able to ping the DG, which I presume is a firewall device or a router, I would check the access-lists on it.

By multi-homed I meant the VM because we could have such problems with miss-configured multiple network adapters on a single server.  
Svet PaperovIT ManagerCommented:
Can you ping the default gateway from the SBS server? Is it multihomed server - mean more than 1 network connection?

Btw, there is no Windows Server 2008 SP3 R1.
gaa18Author Commented:
sorry i meant sp1.

the sbs server can ping default gateway and other machines.

in the physical server 2008 there is 2 network connections. 1 which consists of a team which is assigned to the hyper-v and the other one is being used by the server
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gaa18Author Commented:
when i say its being used by the server i mean it is being used by the physical server 2008
The 4 nic team is being used for the Hyper-V external network.
Just so you are aware, MS will not support you if you use teams for Hyper-V.

That aside, when you say a balancing team, do you mean e.g. smart load balancing or is it LACP (Link aggreation /802.3ad) team. Also, are there VLANs configured and are the VMs tagged in their NICs?

Are the VMs in the same IP Subnet as the host/physical switch/firewall etc.
gaa18Author Commented:
correction cannot ping the gateway!

i think this has to do with the fact that sthe server 2008 has 2 ip addresses (1 for hyper v and 1 for the server itself)

if i team all the nics into one team will it effect server manageability?
Svet PaperovIT ManagerCommented:
Which server has 2 IP addresses – the Hyper-V or the Virtual machine?

Basically, in such design we choose one NIC on the physical server for management only (without creating a virtual adapter from it) and another for the virtual traffic only. You need to clear “Allow management operation system…” for that virtual adapter in Virtual Network Manager as it is shown in the attachment

gaa18Author Commented:

the above is only relevent to server 2008 R2 as the management facility is not available on R1

they hyper-v has the 2 addresses
Svet PaperovIT ManagerCommented:
Sorry, my bad, I am using R2.

The IP addresses on the Hyper-V server do not affect the Virtual Machine. You can, however, disable theIPv4 and IPv6 bindings on the teamed NIC that is used by the virtual machines.

You need to verify if you are using some offload features on the teamed NIC. They could affect the connection.

Did you tested to connect the virtual machine via the single NIC instead of the teamed?
I am not an expert in Hyoer-V, but I do know some other virtualization systems.
If there is a notion of Bridged or NAT'ed NICs in hyper-V, you may want to check that you are using the right one. Bridged may be best for you, then your virtual instances are in the same subnet as the physical host.
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