Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Michael — Mon, 04 Mar 2013 02:24:54 GMT

Check your firewall specifically for port 135 TCP streams coming from you Hyper-v Server.

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Levis Parker — Wed, 14 Dec 2011 19:34:12 GMT

I'm having essentially the same problem; here are my specific details:

• Hyper-V Server 2008 R2 -64 on an Intel DP55 (current generation) motherboard

• No teaming, no VPN, all remote management services enabled

• All machines members of my Domain which works fine in all aspects; DNS servers set to DC

• Management via a fresh Windows 7 machine, which seems to behave normally in all ways

I was able to create a VM via the onboard NIC. After I then configured a virtual network, the VM immediately froze and timed out. When I tried to reconnect, I got "The computer <computer name> failed to perform the requested operation because the RPC call failed."

Could not RDP or Server Manager into the Hyper-V machine.

Then I installed a second NIC in the Hyper-V server machine. Connecting via that NIC, everything works fine, creating a virtual network, adding both NICs to the VM's hardware config, running the VM, everything.

When I unplug the PCI NIC and plug in the onboard NIC, it's back to the same problem.

I ran the "Netsh firewall set opmode disable" on the Hyper-V server machine, turning off its firewall. Now when I try to connect to the the Hyper-V machine via its onboard NIC I get a new error:

"Cannot connect to the RPC server on <%machine>. Make sure your RPC service is running."

When I use the PCI NIC instead, everything still works fine.

Clues greatly appreciated, thanks.

http://www.hypervhd.com

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Robert Veendorp (NL) — Wed, 28 Sep 2011 15:20:15 GMT

With ISA 2006 you should create 2 rules (1st from VPN clients to HVS and 2nd HVS to VPN clients) and then right click on each rule and deselect 'enforce strict RPC compliance'.

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

John Howard -MSFT — Thu, 25 Mar 2010 22:21:09 GMT

Roger, thank you :)

Yes, this is entirely expected if a one-way trust is in place.

Thanks,

John.

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Roger — Wed, 10 Mar 2010 14:55:57 GMT

First of all. Thank you for a wonderfull tool.

In our environment, where the Hyper-V host is in a separate AD forest with a one-way trust from the remote management computer, we had to enable anonymous dcom on the client. The trust restricted the hyper-v host to authenticate to the client.

When trying cscript hvremote.wsf /show /target:hyper-v-host from the client, we got an error on test 7 (async notification query).

Running cscript hvremote.wsf /anondcom:grant on the client resolved the issue, on both LAN, WLAN and VPN connections.

This sadly reduces the security of the client, so we're not sure wheter we're going to keep this configuration or not.

Environment:

Win 2008 R2 Datacenter Hyper-V host, member of trusting AD forest

Win7 remote management computer, member of trusted AD forest

Roger

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

John Howard -MSFT — Tue, 24 Nov 2009 15:33:50 GMT

Prahalad - This is probably your firewall (or router) blocking traffic between the LAN and DMZ. As Hyper-V manager requires callbacks from the server which are not strictly required for scripting, that is what is probably failing here. If you can't route WMI callbacks from your DMZ back to your LAN, another option is to put the host itself on the LAN using one NIC, and the VMs in the DMZ on another NIC. In many ways, this is a more secure option regardless.

Thanks,

John.

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Prahalad — Fri, 06 Nov 2009 12:31:24 GMT

Hi John,

I have the same situation except that I see this in a perimeter host. First I get the RPC error then if I refresh, I see the "No virtual machines" error. interestingly , I can create and change Virtual networks, look and inspect vhd's but the actual VM never shows up. Any ideas?

Another interesting this is I can see the vm using powershell/wmi scripting.

My environment

Hyper-V manager inside LAN on a Win 2008 R2

Host and VM in a DMZ running Win 2008 R2.

Any pointers in resolving this is greatly appreciated.

Prahalad

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Prahalad — Thu, 05 Nov 2009 20:25:00 GMT

Hi John,

Another interesting this is I can see the vm using powershell/wmi scripting.

My environment

Hyper-V manager in side LAN on a Win 2008 R2

Host and VM in a DMZ running Win 2008 R2.

Any pointer is greatly appreciated.

Prahalad

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Chris Porosky — Thu, 29 Oct 2009 22:16:39 GMT

Excellent job - worked like a charm!

re: Hyper-V: Why does Hyper-V Manager not always work over VPN connection? Access Denied or RPC server unavailable errors.

Richard Harvey — Wed, 23 Sep 2009 08:57:17 GMT

Hi,

This dns fix works ok for me, but I left off the dns suffix details as they are both in the same domain.

Thanks, Richard