Asus AC88U RDP Not Working

Zer0Cool

Router: Asus RT-AC88U (stock firmware 3.0.0.4.380_4180)

Running OpenVPN server via the AC88U router.

Issue: I am trying to setup OpenVPN on my AC88U so I can avoid opening ports on the router for RDP and web gui control of a few programs on my home server. I will be connecting via an Android phone (Pixel XL) using the OpenVPN Client and MS official RDP program. Currently the phone connects to the VPN (with an 10.x.x.x IP) but RDP doesnt connect, says it cant find the computer.

The machine I am attempting to login to is a Windows Server 2012 R2 machine on my home network (home server). It is a domain network.

OpenVPN/Router settings:

Interface Type: TUN
Protocol: UDP
Server Port: 1194
Firewall: Auto
Authorization Mode: TLS
Username / Password Auth. Only: No
Extra HMAC authorization: Disabled
VPN Subnet / Netmask: 10.8.0.0 | 255.255.255.0
Poll Interval: 0 (mins)
Push LAN to clients Yes
Direct clients to redirect Internet traffic Yes (also tried no)
Respond to DNS Yes (also tried no)
Advertise DNS to clients: Yes (also tried no)
Encryption cipher: Auto
Compression: Adaptive
TLS Renegotiation Time: -1
Manage Client-Specific Options: No

Ive tried variations (noted above) too. They seem to make no difference. My understanding is that with PUSH LAN to clients my phone should get a local IP on my network, 192.168.1.x but this doesnt happen which is likely why RDP doesnt connect.

Any help would be great. Ive been at setting up my new router for 2 days through various issues (of my own fault) and the last issue I have is being able to securely RDP to my server from outside my network. If I missed any required info let me know. Thanks

PS: I havent opened any ports on the router. Is that something I need to do for this to work?

TinCanTech

Can you ping the vpn server and the remote windows pc ?

Zer0Cool

I presume you mean remotely while connected via VPN?

While on 4G from my phone while connected to VPN i was able to ping both my VPN Server (router) and my remote machine (Win Server 2012) by their local IP's (192.168.1.x).

Was this what you were asking?

Still havent figured out how to get this to work. Everything I have googled seems to indicate having "Push LAN to clients" enabled should allow me to RDP. Any further help would be great. Thanks

TinCanTech

Zer0Cool wroteI presume you mean remotely while connected via VPN?

Why else would you be asking on openvpn forum ..

Zer0Cool wroteWhile on 4G from my phone while connected to VPN i was able to ping both my VPN Server (router) and my remote machine (Win Server 2012) by their local IP's (192.168.1.x).

Then the VPN is working .. check your windows firewall.

Jlennemann

Have you tried to RDP from a Windows machine connected to the VPN? I noticed you said you tested ICMP from your cell phone. If so, then I also believe you have a firewall issue. If you're pushing the LAN to clients then it will not be a port forwarding issue, because you're technically on the LAN even though it's from a remote location so you're not external to the network. You also stated this is a domain network. Make sure your Windows machine is on the same domain as your server.

Zer0Cool

Thanks all.

When I get home today, as a test, I am going to temporarily disable Windows firewall and attempt to connect. If I can then obviously its the Windows firewall and I can try and sort that out. If not Id have to consider other possibilities.

I havent tried from another computer yet as I havent been able to use another computer off my own network (remote) to test it out (locally RDP works fine using the program or Win 10 app). I have a Surface Pro 3 that I installed the VPN client on and maybe I could try it at someone elses house, but I do not know how long before I have a chance to try it.

It is a domain network. My server (Win 2012 r2 Essentials) is the DC, and I have a desktop and the Surface Pro 3 on the domain (Both Win 10 Pro). Long story short, before upgrading my router I had the rdp port forwarded and could RDP remotely without issue. This of course wasnt the best idea on my part. With my current router I can RDP from either PC while connected to my LAN. Now that I think about it I am not sure if my phone can RDP when connected to wifi anymore (ill test this today when Im home as well).

When I go to details in the OpenVPN client on my phone (on 4G) it says im on a subnet 10.x.x.x, not the 192.168.1.x of my network. My understanding is that Push LAN to clients should have me getting on the same subnet, but ill be the first to admit this VPN setup is very new to me.

Ill try out a few things and post back results asap. Thanks

Jlennemann

The 10.X.X.X subnet is your private range assigned to your VPN clients. Behind the scene, depending on how you configured your openvpn server, an ip route will be established directing traffic from 10.X.X.X to 192.168.1.X. I see that you do have push LAN to clients. This will establish your ip route automatically for you. We both have routers made by Asus. I'm sure we can figure this out together.

Zer0Cool

So couple things.

Phone does connect RDP when on wifi.

Disabled Windows firewall and the phone will not connect RDP via 4G/OpenVPN (VPN connects just fine). Still cannot find the computer. So not to be argumentative but I dont see how it can be the firewall (Win firewall) if its not turned on. To be honest I was hoping this was it because itd likely be something I could fix easily.

Any other ideas?

Zer0Cool

OK so um...now its suddenly working...with the firewall re-enabled and no other changes. Thanks all for the input!