I’m encountering a strange problem here. On my local homeserver(Debian 9.9), speedtest-cli and it’s python pendant are freaking slow. Since I use it to monitor my ISP connection stability, this is a problem.
My first thought was my server or speedtest in general have a problem, but here starts the fun part.
Speedtest from my PC(Windows 10), directly connected to the router:
fast.com 370 Mbit/s speedtest.net(server 15819) 242 Mbit/s down, 50,78 Mbit/s up
Speedtest from my notebook(Arch Linux), directly connected to the router:
fast.com 310 Mbit/s speedtest.net(server 15819) 240 Mbit/s down, 50,8 Mbit/s up.
So far so good, but regarding the Debian server, directly connected to the router:
speedtest-cli(server 15819) 3,88 Mbit/s down, 3,69Mbit/s up
So maybe the server is broken… But no, the connection speed is just fine.
wget --output-document=/dev/null https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/debian-9.9.0-amd64-netinst.iso leads to a download speed of about 200 Mbit/s.
Speedtest directly on the router too results in about 250 Mbit/s.
I already tried pruging speedtest-cli, rebooting the server and so on.
Any idea what is going on here? How is it possible, the commandline spedtest fails this spectacular, while the rest of the network setup is just fine?