extremely slow download/upload SoftEther VPN Server on Windows maschine

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softvpnchris
Posts: 4
Joined: Wed Feb 24, 2021 5:13 pm

extremely slow download/upload SoftEther VPN Server on Windows maschine

Post by softvpnchris » Wed Feb 24, 2021 5:33 pm

Hi @all,
I’m new in the SoftEther VPN space and have setup a new SoftEther VPN Server on a Windows 2012 Server R2 (virtual machine).
I'm using client certificates for the authentication but this is not the problem because I have test it also with username and password.
The network traffic speed test tool shows 66 Mbytes in the download direction and 78 Mbytes in the upload direction but if I connect the vpn server with a windows client and run a speedtest, I have only 2 MBit download and 4 MBit upload speed.
In generel I have on the Server side a 300 MBit download and 100 MBit Upload connection and on the client side a 100 MBit Download and 40 MBit Upload connection. I do not set any security police for the vpn users so no bandwidth limitations.
Do someone have an idee why the connection is so slow? with 2 MBit/s it is unfortunately not usable for us :-(

Thanks in advance
Chris

nobody12
Posts: 56
Joined: Sat Feb 13, 2021 10:22 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by nobody12 » Wed Feb 24, 2021 8:03 pm

Have you tried using a client which has a different internet connection/provider?
Check your CPU load on the SE server.
What kind of internet connection is used at the Server?
Problems might arise because of:
Internet connection with high latency (cable,wireless, sattelite)
Things like ProviderNAT/ipv4Lite (you have only IPv6 and the IPv4 you use is shared with others at the providers data center).

I have good experience using a virtual machine based on server 2012R2 and 2016 using a ADSL line with 100down 40up, connected to a client which uses LTE I have about 30+Mbits down to the client and 20up.

lawsangel
Posts: 15
Joined: Fri Feb 19, 2021 6:04 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by lawsangel » Thu Feb 25, 2021 4:34 pm

Which protocal are you using?
Are you connecting directly with open ports or NAT Traversal?
How are you routing the client, via the remote server or the local router?
When you run a speed test, which public IP does it show, the clients or the servers?
Are you connecting to a bridged connection, or are you using secureNAT (Virtual DHCP)

Give us as much information as possible and someone may be able to assist.

softvpnchris
Posts: 4
Joined: Wed Feb 24, 2021 5:13 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by softvpnchris » Thu Feb 25, 2021 7:11 pm

Hi and thank you for going throe my problem.
Some technical information about the infrastructure:
Server Side:
Server 2012 R2 (Hyper-V VM)
Fibre Channel ADSL with 300 Mbit/s Down and 150 Mbit/s up
Dual Stack Connection but the ipv4 is only accessible from the IPS Network, so
we rent a public ipv4 and this address is forwarded to the static ipv4 address we get from the ISP.
I use the public ipv4 address and forward a TCP port to my SoftEther VN Server.
The connection can be established and I get a ipv4 address from the dhcp server.
CPU Load and everything else from the resources side is fine.

SoftEther Speed Test results:
Average Throughput in Download Direction: 99,09 Mbps
Average Throughput in Upload Direction: 41,52 Mbps
Total Average Throughput: 140,61 Mbps

I try both methods so bridged connection and secureNAT (Virtual DHCP) but I have the same issue
for both. I can access the local network and also the internet so this work fine.
The only problem is the speed. I have something between 4 and 6 Mbit down and 8-10 Mbit up.

Client Side:
Windows 10 pro
ADSL 100 Mbit/s down and 40 Mbit/s up
SoftEther VPN Client
Thanks and best regards
Chris

lawsangel
Posts: 15
Joined: Fri Feb 19, 2021 6:04 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by lawsangel » Thu Feb 25, 2021 7:37 pm

My personal preference is to use a bridge connection and to have the internet traffic routed to the local network.

Can you try setting your virtual network adapter to a higher metric than your other network adapters (I usually set mine to 200)
See if that makes any difference.

nobody12
Posts: 56
Joined: Sat Feb 13, 2021 10:22 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by nobody12 » Thu Feb 25, 2021 9:09 pm

Dual Stack Connection but the ipv4 is only accessible from the IPS Network, so
we rent a public ipv4 and this address is forwarded to the static ipv4 address we get from the ISP.
How do you know that the machine which forwards the traffic is able to handle the needed bandwidth?

softvpnchris
Posts: 4
Joined: Wed Feb 24, 2021 5:13 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by softvpnchris » Fri Feb 26, 2021 12:49 pm

nobody12 wrote:
Thu Feb 25, 2021 9:09 pm
now that the machine which forwards the traffic is able to handle the needed bandwidth?
SoftEther Speed Test results:
Average Throughput in Download Direction: 99,09 Mbps
Average Throughput in Upload Direction: 41,52 Mbps
Total Average Throughput: 140,61 Mbps
OF course i can test the bandwidth via diefernt protocols like ftp, ssh, etc.

@lawsangel
how do you setup the SoftEther Server/Client to use the local internet connection for the client but have also the posibiliti to accerss VPN
Destinations using the device name (without changeing the Host file on client side) can i set this somewhere.
Sorry but this is my first SoftEther installation :-(

Client:
Local Lan
192.168.150.x Internet Gateway 192.168.150.1 DNS Server 192.168.150.1
VPN NIC:
192.168.200.x Internet Gateway 192.168.200.1 DNS Server 192.168.200.200

At the moment all the traffic is routet over the VPN Network also the internet connection is using the VPN Gateway 192.168.200.1 and the DNS Server
is also the VPN DNS Server 192.168.200.200. Of course i would like to have on client side the local dns server in use and use only the VPN Dns server or a routing table for devices on the VPN Network

lawsangel
Posts: 15
Joined: Fri Feb 19, 2021 6:04 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by lawsangel » Fri Feb 26, 2021 3:53 pm

@softvpnchris
@lawsangel
how do you setup the SoftEther Server/Client to use the local internet connection for the client but have also the posibiliti to accerss VPN
Destinations using the device name (without changeing the Host file on client side) can i set this somewhere.
Sorry but this is my first SoftEther installation :-(
I think official way to do it, is enabling "No Adjustments of the Routing Table" within the advance settings on the SoftEther Client.
This has never worked for me though.
I find that the only way i can get this to work is to make the virtual network adapter have a higher metric than the other network adapters.
In my case, i usually set it to 200 which works everytime.

Right Click on the virtual network adapter.
Properties.
TCP/IPv4 > Properties
Advanced
Interface metric = 200

https://www.softether.org/4-docs/1-manu ... nformation
11.3.23

nobody12
Posts: 56
Joined: Sat Feb 13, 2021 10:22 pm

Re: extrem slow download/upload SoftEther VPN Server on Windows maschine

Post by nobody12 » Sat Feb 27, 2021 9:50 am

now that the machine which forwards the traffic is able to handle the needed bandwidth?

SoftEther Speed Test results:
Average Throughput in Download Direction: 99,09 Mbps
Average Throughput in Upload Direction: 41,52 Mbps
Total Average Throughput: 140,61 Mbps
OF course i can test the bandwidth via diefernt protocols like ftp, ssh, etc.
I think to create a realistic speed testsyou should setup the Softether Server as Speedtest-server (using a reachable port). Then go to the client you use for VPN, there exectute the speedtest as the client, Enter the ipV4 you have (which forwards your traffic to the SoftEther server) as destination.

Also, regarding a better speed: dont forget to check the Number of TCP connections your client will use, and enable the half duplex mode.
Image

The speedtest enables you also to test a number of N connections, so if you find an optimum with the speedtest you should set the value in the advanced settings according to it.

softvpnchris
Posts: 4
Joined: Wed Feb 24, 2021 5:13 pm

Re: extremely slow download/upload SoftEther VPN Server on Windows maschine

Post by softvpnchris » Sun Feb 28, 2021 4:27 pm

Hi, thanks also for your feedback.

I use the following Tool to make the speedtest:
SoftEther Speed_test.png
The Results of the Speedtest are the following:
SoftEther Speed.png
After i Connect to the VPN the maximum Speed of my connection is the following:
SoftEther Speed_connected.png
The Client internet connection is not the problem because i test 5 different clients on different destinations ant the maximum speed over vpn is similar. I've test also different seetings for the maximum count of tcp connections but without any big improvments if i use something between 16 and 32.


Is there a possibility to use ipv6 to connect to the SoftEther Server?

Thanks.. Chris
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nobody12
Posts: 56
Joined: Sat Feb 13, 2021 10:22 pm

Re: extremely slow download/upload SoftEther VPN Server on Windows maschine

Post by nobody12 » Sun Feb 28, 2021 5:42 pm

Again my Question from the beginning:
When You launch the network traffic speedtest tool on your client.
You choose the "test client" option, and you fill in your own SE servers public IP in the "destination test server hostname" field?
And on your own SE server you launch the Network traffic speedtest tool, set it to the test server mode, choose a free forwarded port.
On the client you also use this port.
Then start the test on the client.

Regarding your test results after establishing the connection:
Remember, that all traffic is routed through your forwading proxy then to the SE Server then to your home internet connection. And back again. I would not expect more then the half amount of the lower value of the upload of one side as the result.

My results I wrote earlier in this topic measured down and upload only against a host inside my own network. That makes a big difference.

When I do a simple internet speed test throught the VPN I have 20down and 10up from my LTE test location. You have the ipv4 forwarding host as an additional problem in this chain. So this is not far away from my results. Instead of investing money in the IPv4 forwarding host, get an ipv4 address. Many providers offer a static IPv4 for a moderate charge on top of the basic tariff. Maybe that will make things better.

But If you dont want to run your Internet traffic through the VPN, Either switch to a SE confguration with a Layer3 Switch and an extra network for the VPN inside your private network where you can setup the server so the client gets not assigned a default route, or tick the box in the SE advanced settings of the client "no adjustment of routing table", SE then will not delete your default route to the internet. However you also you have to manually change the priority of your default gateway so that the gateway to the internet has a higher priority then the SE VPN connection. Lower numbers of the metric value mean higher priority.

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