Wi-Fi download speed locked at 100 Mbit while upload is at >600 Mbit

[MarcelCliff]

Hi,

 

when accessing unRAID via 5 GHz Wi-Fi, download speeds from Docker containers running on unRAID (e.g. librespeed) or of data via SMB/NFS is locked to 100 Mbit.

I tested this on multiple devices and I can see the same on all of them.

The strange thing is, that the upload speed to the unRAID server seems fine with ~600-700 Mbit.

After testing the connection to unRAID, I also ran an Internet speed test using fast.com, which shows me download speeds of ~600-700 Mbit (I've got an 1 Gbit/s Internet plan).

 

The unRAID server is connected via a Cat 6 Ethernet cable to my Fritzbox Router, and when connecting the same clients via Ethernet, the full 1Gbit/s are being used.

Result using librespeed:

 

Any ideas what is going on here?

gandalf-diagnostics-20230123-1931.zip

Edited January 23, 2023 by MarcelCliff

[MarcelCliff]

I was digging a little bit more into this issue:

Using iperf3 I can see the same behavior, even on an Ubuntu 22.04 live OS.

Therefore, I'm quite sure that this is a hardware / driver issue with the Realtek RTL8125B NIC on my Biostar B760M-Silver Mainboard.

Unfortunately, I didn't find a way to disable the 2,5 Gbps mode in the BIOS, to see if this fixes the issue.
I ordered a PCIe Intel I225-V NIC to see if this solves the issue.

[MarcelCliff]

After installing the Intel I225-V NIC, I see the same issue.

I now also tested the connection between my WiFi Macbook and a wired PC -> same issue.

I'm quite sure now that the issue is caused by my Router.

Edited January 27, 2023 by MarcelCliff

[MarcelCliff]

I reported the issue to AVM. Their support response wasn't really helpful.

However, I also reported the issue including diagnostic data through the Fritzbox UI of the beta firmware I was using.

 

I've never received an answer for this report, but the issue is fixed now. I guess an automatic firmware upgrade resolved it.

Unfortunately, I wasn't monitoring the issue close enough to prove this.