VPN Super Slow

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ccmks
Posts: 10
Joined: Sun May 24, 2015 6:01 am

VPN Super Slow

Post by ccmks » Sun Jul 26, 2020 2:37 pm

Hello,

I have installed softether on OVH Public Cloud and they were running fine for years. However, since 2 days ago, my client reported slow VPN speed which is only 1 - 2 Mbps only regardless they are using SecureNAT or Local Bridge. We didn't make any changes on the server side and trying to figure out what slowing down the connection. Our server has 100 Mbps up and down and my client get 50 Mbps down and 10 Mbps up. In the past, they were getting around 48 Mbps when connected to softether VPN, which is reasonable. However, the problem occurred 2 days ago.

Here is what our test so far:
We tested use all kinds of protocol such as Softether VPN windows, L2TP, SSTP and OpenVPN, all of them are still giving slow speed
We changed the ports for VPN to see if there is anyway to improve it, still getting slow speed
We checked the CPU usage and they are not close to 30% of CPU utilization.
We created new instance on OVH then install softether, cient still getting slow speed
This issue only happened on all OVH datacenter and regardless which region they are, client still getting slow speed
We advised client to change their ISP, still getting slow throughput
We boot up instance in Amazon Light Sail and Linode, and install Softether there, no problem so far.
We created OpenVPN instance in OVH public cloud just to compare with Softether, OpenVPN is giving better throughput, around 49 Mbps

The reason we don't want to move to another vendor and stay with OVH is because they need to have access to their resource in OVH datacenter.

What I still can't figure out that why Softether all of sudden is slowing down in last 2 days and it was OK before that.

Yes, I know that VPN will not give 100% throughput of the ISP throughput, but getting 1 Mbps is just not acceptable for 50 Mbps ISP connection.

Any thought would be appreciated

Thank you

drkrool
Posts: 93
Joined: Mon May 25, 2020 4:38 am
Location: Quebec, Canada

Re: VPN Super Slow

Post by drkrool » Mon Jul 27, 2020 1:37 pm

Is the server using linux (or unix-like) or windows?

I've only seen similar issue on a friend's linux server, but never had a ton of access to it to diagnose it

He deployed the exact same softether on a windows and the problem was gone.

ccmks
Posts: 10
Joined: Sun May 24, 2015 6:01 am

Re: VPN Super Slow

Post by ccmks » Tue Jul 28, 2020 1:44 pm

It is a linux based on Centos. I forgot to mention that, I also tried to re-install Ubuntu and install softether, keep having same problem.

I might try to install Windows. That's a good idea although I love linux due to its small footprint and simplicity to deploy and very inexpensive on VPS cost.

ccmks
Posts: 10
Joined: Sun May 24, 2015 6:01 am

Re: VPN Super Slow

Post by ccmks » Tue Jul 28, 2020 3:39 pm

Just so let you know that I have installed Windows on OVH Public cloud and it is working OK. The speed is back to normal on Windows.

Now it is more puzzling, that what happened to the Linux server. Why all of sudden the speed drop to unreasonable speed which it was working fine on several days ago?!

drkrool
Posts: 93
Joined: Mon May 25, 2020 4:38 am
Location: Quebec, Canada

Re: VPN Super Slow

Post by drkrool » Thu Jul 30, 2020 1:18 pm

I can confirm my linux setup is working at full speed, however my friend who had this problem had tried different distros without any luck, only windows did it before he switched to another machine. It's a very weird bug, let me know if you ever figure it out..!

ccmks
Posts: 10
Joined: Sun May 24, 2015 6:01 am

Re: VPN Super Slow

Post by ccmks » Sat Aug 01, 2020 5:48 am

From what I have tried so far, only the Linux on OVH server are affected. I have tried Vultr, AWS Lightsail, Linode and none of them having the problem on Linux.

I was hopping that someone from the developer could figure out what the problem is, because rent Windows VPS is twice more expensive compare to Linux one.

dengb
Posts: 2
Joined: Sat Aug 15, 2020 1:09 pm

Re: VPN Super Slow

Post by dengb » Sat Aug 15, 2020 3:35 pm

Last month, I also encountered this situation in CentOS of Alibaba Cloud. I don’t know the reason, access timed out.

Nickimathew
Posts: 1
Joined: Tue Aug 18, 2020 9:36 am

Re: VPN Super Slow

Post by Nickimathew » Tue Aug 25, 2020 5:44 am

It's a bizarre bug, I can affirm my linux arrangement is working at max throttle, anyway I also had this issue had attempted distinctive distros with no karma, just windows did it before I changed to another machine.

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