Windows Server 2019 outside connections limited to ~1.5megabits per second

Question

Hello everyone :)

I am having a very strange issue with my Windows Server 2019 machine.

I run a few static sites on IIS, including a couple "directory listing" sites where I regularly download files from.

I also have a FTP server on IIS.

I also run a nextcloud install on a virtualbox machine.

The problem I am experiencing is that whenever I am transferring files from OUTSIDE of my LAN/Wifi network, my speeds are being limited to around 1.5 megabits per second.

I experience this when:

-uploading or downloading files from the IIS FTP server via filezilla client.

-downloading files from my IIS "directory listing" website.

-downloading or uploading files to my virtualbox nextcloud deployment.

it seems any connection to the server from outside my wifi network is being severely throttled.

When I am on the same internet connection as the server machine, I do not experience any such problem.

it only happens when I am connecting from any other wifi network when I am out and about.

when I download a single file the speed is anywhere between 0.5-1.5 megabits.

when downloading two files, that speed cuts in half, confirming that there is some type of throttle speed per-user.

does anyone know what it could possibly be? I double checked my IIS settings for the ftp server and my directory listing server and I made sure that the "limits" are not enabled.

I couldn't find anything in my windows firewall that could be causing this, but I may have missed something.

It is definetely not my network connection or server specs. a speedtest on the server's network connection shows 300down and 20up. The machine is hardwired to the router through ethernet. I am the only person using this server.

i've got dual 6-core xeons and 80gb RAM. So shouldn't be a network or hardware issue.

AGAIN this ONLY happens OUTSIDE of my LAN network, when I am on a separate wifi network.

I am pulling my hair out!!!! plz help :(

Answer 1

Some ISPs may throttle specific types of traffic or ports. Check with your ISP to ensure they are not imposing any restrictions on FTP or other services.