I'm at a loss on what is impacting my Unraid download speed as reported by SpeedTest. Here is what I'm seeing:

Yesterday noon, I reverted back to bonding my 2 NIC ports with balance-alb (mode 6) and rebooted. Speedtests were great all day yesterday for almost 24 hours. This has worked well for me for years but recently would drop to unusually slow downloads and not recover until a reboot. As you can see, I'm again experiencing a drop in inbound speeds.

Here is what Unraid currently shows for bond0 for a Speedtest and for a local Iperf test:

My Unraid server has both ports connected to an unmanaged switch with a single connection to the router. The Iperf client (Windows 11 desktop) above is connected to the same unmanaged switch. Speedtests from the Windows 11 desktop get the same ~900Mb up and down.

I'm at a loss for how to narrow down what is happening. All of my attempts before I reverted (replacing cables, disabling bonding, etc) were only making the problem worse as you can see from before noon yesterday.

Any suggestions?

Also wanted to point out that before posting this, I had already upgraded to 7.1.4 because I saw that others were experiencing network issues with 7.1.3. But the problem remains.

Reboot definitely resolves the problem (at least temporarily!):

Any help on this? I'm still experiencing the problem. I don't ever recall experiencing this problem until upgrading to 7.1 (I'm on 7.1.4 now because I saw networking fixes in that release). Here is the chart over the last 4 days before I rebooted this morning:

You have two NICs connected to your unmanaged switch? Disconnect one of those connections and retest.

Thanks for the reply, WN1X! I pulled the eth1 connection and rebooted the UNRAID server. Unfortunately, download performance didn't recover like it has after reboots when both were connected. I'm now getting consistently low download performance. Here is the graph from the UNRAID dashboard for the latest speed test with one port still connected. Would it help to turn off network bonding entirely? Or is there another log or statistic I can look at to troubleshoot?

Another update and still looking for a solution...

As suggested by @WN1X , I removed the cable from eth1 and noticed consistently slower downloads around 100 Mbps. I then modified UNRAID network settings and turned off port bonding so that only eth0 is being used and rebooted. I'm still seeing consistent 100 Mbps down and 900 Mbps up with speed tests from the UNRAID server. If I was getting 100 Mbps both directions, I might think it was a hardware or cable issue that was forcing the NIC to 100Mbps. But 900Mbps upload doesn't fit that hypothesis.

The thought occurred to me the other day that, as a heavy data user, my ISP may be capping download speeds after crossing some usage threshold. But a speed test from my desktop still shows the expected ~900 Mbps up AND down. And with both ports connected in UNRAID, I would see normal speeds in both directions after reboot (at least for a while). Any other ideas?