ASUS RT-AC51U OK as VPN gateway for TV-streaming?

BosseSwede

Regular Contributor
I am helping my brother-in-law to set up a Chromecast TV streaming system for his second home abroad. He has been using satellite TV until end of last year when the provider switched satellite and coverage disappeared.
After that he has been using VPN to my home system and then the Viasat app on his tablet to view the TV programs. Not really ideal.

The plan now is to use a second router in his flat (fiber is already available) which will be configured as a VPN gateway to my home system (I run an OpenVPN server for myself).
Then the Chromecast will be configured to use that router's WiFi and thus be geolocated in Sweden.
He will connect his phone to the same WiFi and then cast the TV show from the apps connected to his TV accounts on to the big screen TV.

Since this is not bleeding edge networking I figured a simple low-end router would work OK.
So I have looked at the ASUS RT-AC51U, which has OpenVPN built-in capability.

Is there any reason to believe that this router would not work for the intended purpose?
 

ColinTaylor

Part of the Furniture
I guess it would depend on how much bandwidth the video stream needs. The choke point might be the VPN speed on the router. But if it's currently working OK on a tablet I guess it's not much.

The RT-AC51U is a very low spec device. Single MIPS processor running at 580 MHz, 100Mb LAN ports and a single stream 5GHz radio. The VPN throughput I guess would be similar to the RT-N66U at ~20Mbps.
 

BosseSwede

Regular Contributor
I think that the needed speed when handling live streams is not really high, I have used Raspberry Pi2 devices in the past as OpenVPN servers to stream geolocated video and it has worked OK. In that case the VPN client had been running on the display device itself (typically a Windows laptop or an iPad) and the device had been connected by VPN to the RPi2 based remote server.
But when using Chromecast this is not possible since for it to run you need the Chromecast and the controlling phone to be on the same WiFi and on the same VPN. Hence the router VPN connection.

Another question:
I just realized that I have an RT-AC51U router set up years ago as an access point extension for my WiFi (the house is 20 m from end to end and wifi was weak in the far end).
It runs f/w 3.0.0.4.380_7378, which is probably outdated by now...

When I check its admin page I cannot see the VPN config, is that hidden if the router runs in AP mode?
Or do I have to update the f/w in order to see it?

I have searched on the ASUS RT-AC51U webpage and I can find a model RT-AC51U firmware update file there. It is 3.0.0.4.380.8591 from 2020-09-22.
Download link here.

Do I need that version in order to see the VPN functions?
(I am waiting for the router for my brother in law to arrive now.)

PS:
Can ASUS routers be commanded remotely to switch on/off VPN connections, i.e. without logging on to the admin GUI interface?
DS
 

ColinTaylor

Part of the Furniture
When I check its admin page I cannot see the VPN config, is that hidden if the router runs in AP mode?
This is the case for other Asus routers that I'm familiar with.
 

BosseSwede

Regular Contributor
OH-BOY!
I found the user's manual on ASUS site and downloaded both for RT-AC51U and RT-AC51Uplus to check the VPN settings.
It turns out that this router only supports PPTP VPN and only as a server!
I.e. it cannot connect to a remote VPN server to allow all router clients access to that server. Basically unusable for my purposes...
Unless the manual is not up-to-date....
Apparently they thought the VPN would be a way to connect back home when away rather than use it as a way to circumvent geolocking...

RESCUE QUESTION:
Can I load some opensource wrt firmware on this device where OpenVPN client is available?
 

ColinTaylor

Part of the Furniture
OH-BOY!
I found the user's manual on ASUS site and downloaded both for RT-AC51U and RT-AC51Uplus to check the VPN settings.
It turns out that this router only supports PPTP VPN and only as a server!
I.e. it cannot connect to a remote VPN server to allow all router clients access to that server. Basically unusable for my purposes...
Unless the manual is not up-to-date....
Rather than keep speculating I suggest you just check it for yourself. I looked inside the firmware image and it does contain the web code for the OpenVPN client. Whether it's actually enabled is impossible to say.


RESCUE QUESTION:
Can I load some opensource wrt firmware on this device where OpenVPN client is available?
Maybe. https://openwrt.org/toh/asus/rt-ac51u
 

ColinTaylor

Part of the Furniture

VPN​

VPN Client L2PT : Yes
VPN Client OVPN : Yes
VPN Client PPTP : Yes
VPN Server IPSec : No
VPN Server OVPN : Yes
VPN Server PPTP : Yes
VPN Fusion : No
 

BosseSwede

Regular Contributor
Thanks Colin!
I will just wait until the RT-AC51U arrives then and fire it up, possibly updating its official firmware and check it out. The advantage if it does work out is that it is a pretty small package device, easy to hide where he has his stuff.

Oh, one last thing:
He will be using this to view Swedish TV via Chromecast so that is why the VPN has to be on the router. However I just realized that if he also wants to view local stuff at other times then he does not want to "be in Sweden"...
Is there a way to send a command to the router (for instance via the ssh interface) to switch VPN Client on/off?
Then I could perhaps make a script for him to toggle Sweden/Local.
Or an app for his phone.
But I guess this low-end router doesn't have such...
 
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ColinTaylor

Part of the Furniture
I have no idea about stock firmware on that device. Merlin's VPN implementation is significantly different. For Merlin you could use something like service start_vpnclient1 and service stop_vpnclient1.
 

BosseSwede

Regular Contributor
I got the RT-AC51U today and have updated it to the latest f/w and started configuring it. Will do the VPN stuff tomorrow.
But I have verified that it supports OpenVPN as client connection.
So that worry is removed at least.
It would be nice to be able to switch off/on the VPN connection in a simple (user friendly) way...
 

BosseSwede

Regular Contributor
If I connect by ssh to the cmd line interface is there then some way to stop/start the openvpn client service?
If there is then perhaps it can be scripted on another Linux device?
 

degrub

Very Senior Member
Is there a phone app for configuring the device ?

If so, maybe run a script from that interface or maybe there is an off/on soft button already ?
 

ColinTaylor

Part of the Furniture
If I connect by ssh to the cmd line interface is there then some way to stop/start the openvpn client service?
If there is then perhaps it can be scripted on another Linux device?
Did you try the answer I gave you in post #9?
 

BosseSwede

Regular Contributor
Did you try the answer I gave you in post #9?
Not yet...
I have not configured the router fully, so no I have not.
But then it looked more like an idea, since your commands looks like pseudocode. I do not know what is running the services in the router to start with, probably not systemd like in Debian Linux, right?
How can I find out?
 

ColinTaylor

Part of the Furniture
Not yet...
I have not configured the router fully, so no I have not.
But then it looked more like an idea, since your commands looks like pseudocode. I do not know what is running the services in the router to start with, probably not systemd like in Debian Linux, right?
How can I find out?
It's not pseudocode. service is the asuswrt command that controls various services. The command examples I gave, as I said, work for Merlin's firmware but I don't know whether they're backward compatible with stock firmware. Merlin's firmware allows for up to 5 VPN client profiles, hence start_vpnclient1. I don't whether that's the same for stock firmware.
 
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BosseSwede

Regular Contributor
OK, but since I could not get SSH running on this router I gave up.
No VPN external ON/OFF switch is possible (at least for me).
Device programmed, tested and works well. Now packed up for transport.
Thanks for the info!
 

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