Extremely slow incoming connection, but outgoing connection is fine over LAN and internet

[ikenji]

Hello, 

Lately I've been experiencing frustratingly slow (5-15mbps) network connection over ethernet. However what's strange is that only the inbound connection is slow, and outbound traffic is not affected. This has been reproducible using many different devices to connect to Unraid as well as a speedtest.net result from a VM running on the server. I'd also like to clarify that the server used to run at full speed in both directions, but the file transfers became slow more recently, though I can't pinpoint it to a specific release due to my set and forget tendencies.

Troubleshooting I have tried so far: 

1. USB 3 NIC
2. Bonding using USB nic and built-in NIC
3. Upgrade to latest version of Unraid
4. Disable Docker (I tested speed by copying file to a share)
5. Disable VMs
6. Run speed test using different PC

The only thing I've considered but have not tried yet is running a different OS on this hardware, and doing a speed test from there
 

Here are some screenshots from my speed tests:

OpenSpeedTest result from another PC over LAN:

 

 

Speed test from VM running on this server: 

Any ideas on how to troubleshoot this problem? I've looked at the logs briefly but don't have the background to separate any useful logs from the noise.

Thank you in advance for the help!
 

tower-diagnostics-20230118-2341.zip

[JorgeB]

Start by running a single stream iperf test in both directions. 

[itimpi]

It might be worth swapping the network cable? 

[ikenji]

11 hours ago, JorgeB said:

Start by running a single stream iperf test in both directions. 

Windows -> Unraid:

PS F:\Downloads\iperf-3.1.3-win64\iperf-3.1.3-win64> .\iperf3.exe -c 192.168.1.78
Connecting to host 192.168.1.78, port 5201
[  4] local 192.168.1.38 port 52606 connected to 192.168.1.78 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.01   sec   384 KBytes  3.12 Mbits/sec
[  4]   1.01-2.00   sec  0.00 Bytes  0.00 bits/sec
[  4]   2.00-3.00   sec   128 KBytes  1.05 Mbits/sec
[  4]   3.00-4.00   sec  0.00 Bytes  0.00 bits/sec
[  4]   4.00-5.01   sec   128 KBytes  1.03 Mbits/sec
[  4]   5.01-6.01   sec  0.00 Bytes  0.00 bits/sec
[  4]   6.01-7.01   sec   128 KBytes  1.05 Mbits/sec
[  4]   7.01-8.00   sec   384 KBytes  3.17 Mbits/sec
[  4]   8.00-9.01   sec   512 KBytes  4.15 Mbits/sec
[  4]   9.01-10.01  sec   256 KBytes  2.10 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.01  sec  1.88 MBytes  1.57 Mbits/sec                  sender
[  4]   0.00-10.01  sec  1.64 MBytes  1.37 Mbits/sec                  receiver

iperf Done.

Unraid -> Windows:

iperf3 -c 192.168.1.38
Connecting to host 192.168.1.38, port 5201
[  5] local 192.168.1.78 port 55320 connected to 192.168.1.38 port 5201
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  79.8 MBytes   669 Mbits/sec  3063    294 KBytes       
[  5]   1.00-2.00   sec   101 MBytes   846 Mbits/sec  4081    120 KBytes       
[  5]   2.00-3.00   sec   103 MBytes   860 Mbits/sec  3956    286 KBytes       
[  5]   3.00-4.00   sec  79.3 MBytes   665 Mbits/sec  3174    294 KBytes       
[  5]   4.00-5.00   sec   102 MBytes   858 Mbits/sec  3860    249 KBytes       
[  5]   5.00-6.00   sec   101 MBytes   844 Mbits/sec  3974    297 KBytes       
[  5]   6.00-7.00   sec   101 MBytes   849 Mbits/sec  4087    151 KBytes       
[  5]   7.00-8.00   sec  81.0 MBytes   679 Mbits/sec  3113    283 KBytes       
[  5]   8.00-9.00   sec  80.2 MBytes   673 Mbits/sec  3267    291 KBytes       
[  5]   9.00-10.00  sec  80.8 MBytes   678 Mbits/sec  3151    146 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   908 MBytes   762 Mbits/sec  35726             sender
[  5]   0.00-10.00  sec   905 MBytes   759 Mbits/sec                  receiver

 

 

 

7 hours ago, itimpi said:

It might be worth swapping the network cable? 

Sorry I forgot to mention, I have tried 3 different network cables.

Thanks for the help so far!

[JorgeB]

iperf test confirms it's a network problem, could be NIC, switch, cables, client PC, etc.

[ikenji]

Hi everyone, thougtht I'd update the thread and close it out, since it seems to be working now. 

The cause was my network switch (HP ProCurve 1800), which I reset to factory settings. 

Thank you everyone for the help, I didn't think this could happen since I hadn't configured any of the features of the switch.