OpenVPN Unstable/Unsable - ISP blocking it?

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BY_Zaca
OpenVpn Newbie
Posts: 3
Joined: Tue Aug 06, 2019 7:32 am

OpenVPN Unstable/Unsable - ISP blocking it?

Post by BY_Zaca » Tue Aug 06, 2019 9:00 am

Hi.

I have a openvpn server running on a dedicated server and it works amazingly fine on a Computer "A" that uses the internet "A".

However, a Computer "B" that uses the internet "B" is unstable on a point that you cant even surf on the internet.

Image

192.168.1.1 = Router gateway
10.10.10.1 = openvpn gateway

I have tried connecting over TCP and UDP, tried changing the default ports to random ports, tried windows and linux, tried different computers from the "Internet B" network, tried connecting the modem directly on the computer and setting up the PPPOE (the ISP uses this protocol to provide internet) to prove that the router was not blocking openvpn, tried lowering the PPPOE and Openvpn MTU, tried different VPN server on a completely different server with a completely different route but still exactly same problem.

Direct TCP and UDP connection from this Computer B to the server where is running the openvpn server is fine, no packet loss and i can get full speed. Things gets bad when i connected on the vpn. The funny thing is that PPTP and L2TP also works fine on this server where openvpn is running.

Any one ever had something similar?
Thanks!

BY_Zaca
OpenVpn Newbie
Posts: 3
Joined: Tue Aug 06, 2019 7:32 am

Re: OpenVPN Unstable/Unsable - ISP blocking it?

Post by BY_Zaca » Fri Sep 06, 2019 9:21 pm

The funny thing is...

If i use a software from VPN providers using openvpn protocol, it is stable and work very well. If i download the openvpn profile file that connect on the same server/encryption and import to use with the native openvpn client, it work very unstable on a point that is umsable like on the photo above.

Any idea on what the issue could be?

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TinCanTech
OpenVPN Protagonist
Posts: 6032
Joined: Fri Jun 03, 2016 1:17 pm

Re: OpenVPN Unstable/Unsable - ISP blocking it?

Post by TinCanTech » Fri Sep 06, 2019 10:57 pm

Your internet B looks to be awful ... but what do we know about internet B ?

BY_Zaca
OpenVpn Newbie
Posts: 3
Joined: Tue Aug 06, 2019 7:32 am

Re: OpenVPN Unstable/Unsable - ISP blocking it?

Post by BY_Zaca » Sat Sep 07, 2019 6:22 am

The internet B is a FTTH 300/150MB (Telefonica, that spanish company) and work very well when not using openvpn. PPTP/L2TP and softwares from vpn providers (using openvpn "protocol") also work very well and i can get full speed. But if i use native openvpn software importing the client file from those vpn providers, it is impossible to use.

Just does not make any sense using same protocol and having completely different performance.
Very weird, any ideas?

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TinCanTech
OpenVPN Protagonist
Posts: 6032
Joined: Fri Jun 03, 2016 1:17 pm

Re: OpenVPN Unstable/Unsable - ISP blocking it?

Post by TinCanTech » Sat Sep 07, 2019 12:48 pm

If you are connecting to your own server See:
viewtopic.php?f=30&t=22603

If you are connecting to a VPN service provider then please contact their support.

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