OpenVPN slows to crawl after 24 hrs

[Chrisgtl]

Anyone have any experience of their OpenVPN slowing to a crawl after 24 hrs uptime using Torguard TCP?

My usual speeds with the above (client 1) is around 70MB/s but after some time it drops to a constant 3MB/s. If I log into my 86U and change it from TCP to UDP the speed goes back to normal. I can then change back from UDP to TCP and everything is fine for another 24 hrs.

How can I diagnose where the problem is?

I'm thinking to leave it on UDP and see if the same problem occurs.

 

[skeal]

Anyone have any experience of their OpenVPN slowing to a crawl after 24 hrs uptime using Torguard TCP?

My usual speeds with the above (client 1) is around 70MB/s but after some time it drops to a constant 3MB/s. If I log into my 86U and change it from TCP to UDP the speed goes back to normal. I can then change back from UDP to TCP and everything is fine for another 24 hrs.

How can I diagnose where the problem is?

I'm thinking to leave it on UDP and see if the same problem occurs.

UDP is the faster of the two protocols.

 

[Chrisgtl]

UDP is the faster of the two protocols.

Absolutely but there is no reason for a TCP VPN connection to slow from 70MB/s to 3MB/s after 24 hours. I've scrapped running OpenVPN on my 86U in favour for running the VPN app on a client basis. I only need VPN for two of my devices so I'm thinking offloading the VPN duties from the router to the client makes sense.

 

[Xentrk]

I've been a TG customer for several years with no issues and only use UDP. I did have to obtain a new dedicated IP this past spring and they wanted me to use TCP. I had issues and asked them to revert back to UDP, which they did. On several occasions, I did have slow vpn performance after performing a firmware upgrade. A factory reset followed by manually reentering config or using the nvram back up and restore utility fixed the issue each time.

 

[skeal]

I've been a TG customer for several years with no issues and only use UDP. I did have to obtain a new dedicated IP this past spring and they wanted me to use TCP. I had issues and asked them to revert back to UDP, which they did. On several occasions, I did have slow vpn performance after performing a firmware upgrade. A factory reset followed by manually reentering config or using the nvram back up and restore utility fixed the issue each time.

+1 I'm a TG customer with dedicated IP as well, runs perfect.

 

[Val D.]

Absolutely but there is no reason for a TCP VPN connection to slow from 70MB/s to 3MB/s after 24 hours.

There is, actually. You are most likely experiencing so called TCP Meltdown when stacking TCP-over-TCP in conditions with packet loss. There are good sources of information what exactly is happening, but here is a short description:
https://openvpn.net/faq/what-is-tcp-meltdown/

If you use Torrent clients with OpenVPN on UDP, make sure you disable µTP protocol. I was fighting with slowdowns from 220-250Mbps to 1-2Mbps through OpenVPN on UDP, took me some time to figure out what's wrong:
https://www.snbforums.com/threads/openvpn-client-udp-connection-issues-solved.58077/

I only need VPN for two of my devices so I'm thinking offloading the VPN duties from the router to the client makes sense.

Indeed, for two devices only it is a better option and more convenient to change the VPN server or to turn the VPN on/off.

 

[wesbez]

Absolutely but there is no reason for a TCP VPN connection to slow from 70MB/s to 3MB/s after 24 hours. I've scrapped running OpenVPN on my 86U in favour for running the VPN app on a client basis. I only need VPN for two of my devices so I'm thinking offloading the VPN duties from the router to the client makes sense.

Have noticed this myself. However even with having OpenVPN on the client I have the same issue. I have to reconnect to get it going again.

 

[Makaveli]

There is, actually. You are most likely experiencing so called TCP Meltdown when stacking TCP-over-TCP in conditions with packet loss. There are good sources of information what exactly is happening, but here is a short description:
https://openvpn.net/faq/what-is-tcp-meltdown/

If you use Torrent clients with OpenVPN on UDP, make sure you disable µTP protocol. I was fighting with slowdowns from 220-250Mbps to 1-2Mbps through OpenVPN on UDP, took me some time to figure out what's wrong:
https://www.snbforums.com/threads/openvpn-client-udp-connection-issues-solved.58077/



Indeed, for two devices only it is a better option and more convenient to change the VPN server or to turn the VPN on/off.

I only have my VPN tunnel up for 1 android device which streams (UDP) and so I will go home and check speeds but haven't noticed an issue I usually leave the tunnel up for a month at a time or will sometimes randomly close it and reconnect when I feel like it. I will have to do a speed test tonight to check if I have the same slow down issue.

I may check running the VPN client directly on the android box since it has the same Arm Cortex-A53 cores that are in the AX88U but has 8 of them instead of the quad in the router maybe worth a test.

 

[Chrisgtl]

There is, actually. You are most likely experiencing so called TCP Meltdown when stacking TCP-over-TCP in conditions with packet loss. There are good sources of information what exactly is happening, but here is a short description:
https://openvpn.net/faq/what-is-tcp-meltdown/

If you use Torrent clients with OpenVPN on UDP, make sure you disable µTP protocol. I was fighting with slowdowns from 220-250Mbps to 1-2Mbps through OpenVPN on UDP, took me some time to figure out what's wrong:
https://www.snbforums.com/threads/openvpn-client-udp-connection-issues-solved.58077/



Indeed, for two devices only it is a better option and more convenient to change the VPN server or to turn the VPN on/off.

Thanks for the info! I did not know this so I stand corrected. I don't use any Torrents of any kind on my network. The two devices I use for VPN are Nvidia Shield TV boxes - I pay for the TorGuard UK Streaming service which ensures things like BBCi Player, Amazon Video, Netflix work.

I've not noticed any slow downs using the TG app instead of running it through my 86U so far - but I probably won't as I put my Nvidia Shield to sleep every night which will reset the TG app.

Interestingly, when running the TG VPN (TCP) thorugh the 86U I got 70MB/s and when running the TG app (TCP) I get 100MB/s.

 

[Chrisgtl]

Have noticed this myself. However even with having OpenVPN on the client I have the same issue. I have to reconnect to get it going again.

Is this with TG on TCP?