Hi  @NewbUser,

From your description, VPN should be working properly on the router now, right? If it is still unstable, I suggest you test OpenVPN Client on other devices to see if it can also connect stably? 

The slow VPN speed on the TP-Link Router when using the VPN Server or VPN Client is often due to the limitations of the router's CPU. The processing power of the router is not as robust as that of a computer or other devices, which can result in slower performance when establishing VPN connections. This limited processing capability of the router is a contributing factor to the slower speeds experienced. To improve VPN performance, you may consider setting up the VPN connection on a computer or other devices that offer more processing power and performance capabilities.

Hi  @Joseph-TP , thank you for your reply. At this point, I have 4 VPN profiles, all identical to each other in every aspect. If I enable one of them (when others are disabled), it will return the "Connecting" status and get stuck with it. However, if I keep disactivating/activating them one after another randomly, at some point one of them would successfully connect to my VPN server. So, in brief, it displays different behaviors with the same type of input, which is bedazzling by itself and gives no guarantee that the VPN continues working on my router.

It looks like the issue, if it is an issue, is router-side, as the same VPN server is easily reached in fractions of seconds from my PC's OpenVPN Connect client. I switched it on and off many times, and it was working with no problems whasoever.

So yes, I guss if I keep it enabled all the time while managing which of the devices has access to it, it will work, but I wonder if it is normal and if it keeps working after a while.

P.S. ...And big thanks for explaining to me the speed issue, I had no idea that it might be processor-related (the difference is really dramatic, e.g. 19/4 Mbps on the router with enabled VPN VS 82/84 Mbps on my rig via the PC OpenVPN client as of today).

Dear All,

I guess the workable solution for this issue (which is, in fact, the router's erratic/inconsistent behavior in terms of connecting to a remote VPN server) is rebooting. In my case, the successful pattern was like this: (1) create a profile; (2) enable it (that is where we get the "Connecting" status, which may last forever, but we disregard that and go on to the next step); (3) reboot the router. When back online, it is highly likely to have the VPN profile enabled and working. As a plan B, you may create several profiles with the same settings and activate/deactivate them in a random order, which may result, at some point, to bringing the VPN connection online. Once it is up, the router stays reliably connected.

As regards the speed issue, I followed a recommendation to change the encryption algorythm from AES-256-CBC to AES-128-GCM in order to unload the router's processor to a degree, but this resulted in a lower speed, contrary to my expectations.

Hi  @NewbUser,

Below is a simple and useful troubleshoot step.  
Please plug a usb to the router. Then add this line to the ovpn file: log-append /tmp/smb/G/log.txt 
Then re-import the ovpn file and run the vpn. You will find the error log in the usb. 
It will be helpful if you could provide the log.  

Please send the log to the email support.forum@tp-link.com, attaching Forum ID 734132 and details, and the senior engineer will assist in analysis and follow-up.

Hi  @Joseph-TP ,

It looks like the problem has gone.

By default, in the Access Server panel, the "Allowed data channel ciphers" box is left blank. I followed a recommendation from the web and specified the accepted ciphers as follows: AES-128-GCM:AES-256-GCM:AES-256-CBC:AES-128-CBC:BF-CBC. That appears to have solved the problem when it comes to activating profiles set up with the config file generatd inside the OpenVPN AS admin panel. The problem persists with an edited file where I have replaced the "cipher AES-256-CBC" string with "cipher AES-128-GCM" and added "auth SHA256" for (allegedly) faster performance, though, but it is not a big issue for me.

Thank you very much for your help!