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Has anyone else seen this behavior?

I have a VPN server (Win2008 R2) with two network interfaces; RRAS is configured on the 'external' interface, and I am RDP'ed into the 'internal' interface. As soon as I start the RRAS service, connectivity to port 3389 on the internal interface is broken.

I can still ping the internal interface (on ipv4 only, but that's another issue); there are no static filters configured for any interface in RRAS (this is the most common cause I've found online for this behavior), and I've completely disabled the Windows host firewall.

As soon as I stop RRAS, I can RDP into the server again without issue.

This link is the closest description of the behavior I've seen, and causes me to suspect some that built-in filtering gets enabled whenever RRAS is started.

Further evidence is the large number of events in the Security event log like the following when I stop the RRAS service:

Log Name: Security Source: Microsoft-Windows-Security-Auditing Date: 7/12/2011 10:59:28 AM Event ID: 5447 Task Category: Other Policy Change Events Level: Information Keywords: Audit Success User: N/A Computer: RRAS.FQDN.com Description: A Windows Filtering Platform filter has been changed.

Subject: Security ID: SYSTEM Account Name: NT AUTHORITY\SYSTEM

Process Information: Process ID: 788

Provider Information: ID: {00000000-0000-0000-0000-000000000000} Name: -

Change Information: Change Type: Delete

Filter Information: ID: {f48ca5fa-0a0b-4c92-8176-f2fec936b1c3} Name: L2TP Server Filter1 Type: Not persistent Run-Time ID: 85255

Layer Information: ID: {5926dfc8-e3cf-4426-a283-dc393f5d0f9d} Name: Inbound Transport v4 Layer Run-Time ID: 12

Callout Information: ID: {5132900d-5e84-4b5f-80e4-01741e81ff10} Name: WFP Built-in IPsec Inbound Transport v4 Layer Callout

Additional Information: Weight: 17321535995904
Conditions: Condition ID: {0c1ba1af-5765-453f-af22-a8f791ac775b} Match value: Equal to Condition value: 0x06a5

Condition ID:   {3971ef2b-623e-4f9a-8cb1-6e79b806b9a7}
Match value:    Equal to
Condition value:    0x11

Condition ID:   {6ec7f6c4-376b-45d7-9e9c-d337cedcd237}
Match value:    Equal to
Condition value:    0x01

Filter Action:  Callout

When I start RRAS, matching events are generated with the Change Type being 'Add' instead.

Can anyone shed some light on what's happening here? I'm fine with RRAS enabling these filters for the external interface, but I'd like to be able to RDP into the server on the internal interface while RRAS is running.

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  • UPDATE -- this appears to be a routing issue, not any filtering like I was suspecting before. I can create a static route for the server subnet to use the server interface and a default gateway of 0.0.0.0 and then the servers can access the VPN server again via ping, RDP, etc. But then the VPN clients lose all connectivity to the server subnet -- which is critical, since this is where the DNS servers are located. How can I configure the routing so that BOTH interfaces can access the server subnet?
    – jbsmith
    Jul 18, 2011 at 17:18

2 Answers 2

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Well, I'm sure there's some way to get it setup exactly as I wanted, but I reconfigured the server to have both NICs on the 'external' subnet (all of our IPs are public - .edu) and reconfigured RRAS VPN and everything is working fine without any additional static routes, etc.

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In addition to making sure Windows Firewall is not blocking RDP... turns out there is another place to allow RDP if you use RRAS as a NAT Gateway.

When I had the same issue (which affected the public interface of RRAS only - I could still RDP via the private or VPN interface) my fix was:

Routing and Remote Access console - (Local) - IPv4 - NAT

Then right-click on the Public interface - Services and Ports tab, and tick Remote Desktop, then edit it and put 127.0.0.1 under Private address.

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