CRS328-24P-4S+ Speed issue

Good Day all

I’m new to the forums. Hope someone can provide us with some advice regarding our issue.

We have a couple of CRS328-24P-4S+ Switches and noticed a speed issue.
We have tested it on RouterOS version 6.44.3 on Firmware Version 6.44.3 and also on SwitchOS Version 2.9, but the same issue keeps popping up.

On the following scenario, we are using a test switch.
Issue is as follow:

  • I connect Computer A in port 1 connected to Switch A. Connecting at 1 Gig speed.
  • I connect Computer B in port 4 connected to Switch A. Connecting at 1 Gig Speed.
  • I’m logged in to computer A and I’m copying a file to Computer B. The file size is almost 4 Gig:
    Coping To.png
  • I’m logged in to computer A and I’m copping a file from Computer B. The files size is almost 4 Gig:
    Copying From.png
    If you observer the above, when we send files, the speed always drops to below 50% capacity. But when you Download, it runs at max capacity. This we have replicated over all our CRS328-24P-4S+ switches. We have the same issue when linking the switch with a fiber connection (Using Ubiquiti UF-SM-10G fiber module). So when talking directly on the same switch from port to port or between switches using a 10 Gig fiber, the issue is the same.

If anyone has any advice or wisdom to share, will be appreciated.

Thank you

Copying a large file between a windows share and local disk is not a scientiffic way of measuring link speed. Scientific way is to use some kind of traffic generator/sink, such as iperf.

It might be interesting to connect the two computers in question directly to each other. I would speculate that what you are seeing is more related to the performance of the computers involved and not the switches. Part of that statement is the difference in performance between upload and download. The switch does not know or care which computer is the source and which computer is the destination - it’s just data. However computers can (and often do) have radically different read vs write capabilities.