On XGS1010-12 The two 10Gb ports cannot be used at the same time for me

mach25 Posts: 3
First Comment
edited August 2022 in Switch
I used an xgs1010-12 to connect my computers to my router and I have a 1.5 Gbp internet service.

Both of the 10Gb sfp+ ports seem to be working fine if used alone.
I used port 12 or port 11 as the uplink connected to my router and both worked.
I could reach the full speed of 1.5 Gbps though a 2.5Gb connection to my PC.

However, if I use port 12 as the uplink connected to my router, and port 11 connected to my PC with a 10Gb sfp+ NIC, I could only get about 300 Mbps.
Note I was able to achieve 1.5 Gbps if connecting my PC to the router directly through the 10Gb sfp+ NIC's on both ends.

So both of the 10 Gb ports seem to be fine. But once I use one as uplink and the other to my PC, I could only reach 300 Mbps instead of 1.5 Gbps.
It's so weird and I was really puzzled.

Any one had similar experience? Any success with both 10Gb ports used at the same time?
Please kindly share your experience or your thoughts.
Thanks a lot in advance!

All Replies

  • Zyxel_Jonas
    Zyxel_Jonas Posts: 313  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    Hi @mach25,

    Welcome to Zyxel Community!

    Thanks for reaching out!

    Before we dive in, can you give me a little more context about the equipment in your LAB including the specific model of NIC (provide version), SFPs, software (provide version) and operating system, therefore I could analyze and trace out what might be the cause you've getting 300 Mbps.

    In addition, I've made a local throughput test, and the result seems normal in my LAB, information as below;

    1) PCA, NIC Intel X540-AT2 (10G), with iPerf3
    2) PCB, NIC Aquantia AQtion 10G, with iPerf3
    3) XGS1010-12
    4) 2x  Zyxel SFP10G-SR

    1) Both 10G SFPs connected to port11 & port12.

    2) Use iPerf to test throughput on both PC using the command below:
    iperf3 -c (IP) -P4 -w 655350 -l 655350 -t 60 -i 60

    Normal: Could reach 9.10 Gb.

  • Thank you so much for your prompt reply with detailed information, Jonas!

    My router is an Intel i3 9100 computer with pfSense v2.4.5-p1 installed.
    It has a dual sfp+ port 10 GbE NIC (Broadcom BCM957810A1006G) and a dual port 2.5 GbE NIC (Realtek RTL8125).
    One of the sfp+ ports is connected with the ONT from my ISP, sync'ed at 2.5 Gbps and the actual speed is 1.5-1.6 Gbps.
    The other sfp+ port is connected to port 12 of my XGS1010-12 by a LC OM3 cable. 

    My PC is an Intel i3 9100 with Windows 10 20H2.
    It has a dual sfp+ port 10 GbE NIC (Dell Y40PH Broadcom 57810S) and a 2.5 GbE NIC (Realtek RTL8125).
    I used a SFP+ DAC Twinax Cable for a 10 Gb link to port 11 of my XGS1010-12.
    I also used a cat 5e cable for a 2.5 Gb link to port 9/10 of my XGS1010-12.

    For my primitive testing I used both the sfp+ and the 2.5 GbE interface but could only get satisfactory speed with the 2.5 GbE NIC.
    I could achieve satisfactory speed (1.5 Gbps) with the sfp+ NIC if it's connected to the router directly (without using XGS1010-12) though.

    I only used Speed Test to measure my internet access speed.
    I will try iPerf for LAN performance benchmark and update this thread once I get a chance tonight.

    Thanks again!