Only getting 2.5Gb one way (and other weird behaviour)

[Ginger Penguin]

Hi all,

 

I've just set up a 2.5Gb connection between my NAS (running TrueNAS) and my desktop. My desktop's motherboard has 2.5Gb onboard but I added in a NIC to the NAS and bought a QNAP 2.5Gb/10Gb switch. I was testing different configurations with iperf3 and at first I realised I was only getting greater than gigabit speeds from the NAS to the desktop. So I decided to try it with the onboard gigabit port both with the new switch and with everything connected to the router as before. Connected to the router I'm getting gigabit speeds both ways fine. If I add the new switch into the mix, however, and connected to the gigabit port on the NAS's motherboard, from the NAS to the desktop is as before but going the other way it slows to a crawl. Confusingly, this all goes away if I'm connected to the new NIC except for the fact that I'm limited to gigabit going from the desktop to the NAS.

 

I've attached screenshots of the iperf3 results below. Any clues as to why these oddities are occurring?

 

Router Only

Spoiler

Desktop to NAS

NAS to Desktop

New Switch (Gb Motherboard)

Spoiler

Desktop to NAS

NAS to Desktop

New Switch + 2.5Gb NIC

Spoiler

Desktop to NAS

NAS to Desktop

That data aside, however, I can't work out if that translates into real world performance as copying off the NAS in either the original or new configuration sits around 90MB/s. This I find odd actually and I think I may have set up my RAID incorrectly which isn't a big issue as I'm doing a whole new array in a few weeks.

[Husky]

Could you try connecting the NAS and your PC directly together with a single cable and running a test that way? Then we can determine whether the switch or one of the machines is at fault.

You could also boot a live operating system from a USB drive on the NAS as well as your PC (such as Ubuntu 22.04 LTS) and run an iperf on both, again, to rule out any issues with drivers and the NICs.

[Ginger Penguin]

4 hours ago, Husky said:

Could you try connecting the NAS and your PC directly together with a single cable and running a test that way? Then we can determine whether the switch or one of the machines is at fault.

You could also boot a live operating system from a USB drive on the NAS as well as your PC (such as Ubuntu 22.04 LTS) and run an iperf on both, again, to rule out any issues with drivers and the NICs.

I gave the directly attaching idea a go and I got the same 1.07Gb/s result with Desktop to NAS but when I tried to go the other way, it just hung and wouldn't do anything. This was the same using both the NIC and the onboard. I went back to Switch+NIC to make sure I hadn't borked anything and it worked fine. NAS to Desktop side actually improved to a solid 2.37Gb/s all the way through as opposed to how fluctuating it was before but no change above 1.07 the other way.

 

I'll try the USB boot idea in the morning and see if that proves helpful.

[Alex Atkin UK]

7 hours ago, W.D. Stevens said:

I gave the directly attaching idea a go and I got the same 1.07Gb/s result with Desktop to NAS but when I tried to go the other way, it just hung and wouldn't do anything. This was the same using both the NIC and the onboard. I went back to Switch+NIC to make sure I hadn't borked anything and it worked fine. NAS to Desktop side actually improved to a solid 2.37Gb/s all the way through as opposed to how fluctuating it was before but no change above 1.07 the other way.

 

I'll try the USB boot idea in the morning and see if that proves helpful.

I really hope its not a Windows problem, I've had this on various PCs before and never could figure out how to fix it.  Always worked perfectly from a Linux USB stick, Windows networking is just a weird beast that seems to randomly break like this for some reason.

[Ginger Penguin]

6 hours ago, Husky said:

You could also boot a live operating system from a USB drive on the NAS as well as your PC (such as Ubuntu 22.04 LTS) and run an iperf on both, again, to rule out any issues with drivers and the NICs.

Well, I gave that a go just now and lo and behold, I was getting 2.35Gb/s both ways so it seems like the hardware is all working fine. I didn't test the weirdness that was going on with the NAS motherboard's ethernet come to think of it, however. Is this likely to be a driver issue, then? If so, on which side?

Just now, Alex Atkin UK said:

I really hope its not a Windows problem, I've had this on various PCs before and never could figure out how to fix it.  Always worked perfectly from a Linux USB stick, Windows networking is just a weird beast that seems to randomly break like this for some reason.

Ah it would seem that this is indeed the case so probably a Windows issue that may or may not be fixable?

[dogwitch]

3 hours ago, W.D. Stevens said:

Well, I gave that a go just now and lo and behold, I was getting 2.35Gb/s both ways so it seems like the hardware is all working fine. I didn't test the weirdness that was going on with the NAS motherboard's ethernet come to think of it, however. Is this likely to be a driver issue, then? If so, on which side?

Ah it would seem that this is indeed the case so probably a Windows issue that may or may not be fixable?

i know windows 10 has issue with trunking a connection.

[Alex Atkin UK]

3 hours ago, W.D. Stevens said:

Ah it would seem that this is indeed the case so probably a Windows issue that may or may not be fixable?

My gaming laptop was particularly problematic, it was literally broken like this with the hardware it came with.  The weird thing was even a fresh install of Windows never fixed it.  I think it may have gone away over time with a Windows Update, so some very specific issues between that hardware and Windows itself.

 

Even on one of my Win11 PCs right now I get 2.37Gbit down, 1.77Gbit up, on any PC with Linux I consistently get full speed, its really weird.

 

Although I might add I have also seen cases where iperf3 gets a slow speed but actual file transfers go faster.

[Ginger Penguin]

Oh my word, it works. So it really seems to have just been a bad Windows driver. Turns out it was about 7 years out of date and wouldn't update so I uninstalled the device and ran the utility downloaded from Realtek's website. iperf gives 2.35Gb both ways and I'm able to copy files to the NAS at full speed. I can't test the other way at the moment presumably due to limitations of my hard drives whereas copying to the NAS goes via the RAM. Hopefully I'll have good news when I put in my new hard drives in a couple of weeks.