Switching

 View Only

IMPORTANT MODERATION NOTICE

This community is currently under full moderation, meaning  all posts will be reviewed before appearing in the community. Please expect a brief delay—there is no need to post multiple times. If your post is rejected, you'll receive an email outlining the reason(s). We've implemented full moderation to control spam. Thank you for your patience and participation.



  • 1.  Bandwidth issue on QFX5100-48S-6Q and HP ProLiant DL380 Gen10 Servers.

    Posted 04-12-2022 11:06
    Hi people,

    I need help with my issue, I have a pair of "QFX5100-48S-6Q" in a Virtual-Chassis, so when I connect my two "HP ProLiant DL380 Gen10 " servers directly to each other and run iperf,
    I get full 10Gb/s throughput. But when I connect these servers via a pair of QFX5100 on same VLAN, throughput is capped to 6Mb/s.  Below is a configuration of the ports in QFX5100 where I connect the servers.

    set interfaces xe-0/0/0 mtu 9214
    set interfaces xe-0/0/0 unit 0 description SERVER1
    set interfaces xe-0/0/0 unit 0 family ethernet-switching interface-mode access
    set interfaces xe-0/0/0 unit 0 family ethernet-switching vlan members VLAN100

    set interfaces xe-0/0/1 mtu 9214
    set interfaces xe-0/0/1 unit 0 description SERVER2
    set interfaces xe-0/0/1 unit 0 family ethernet-switching interface-mode access
    set interfaces xe-0/0/1 unit 0 family ethernet-switching vlan members VLAN100

     The switches are running Junos: 18.1R3-S6.1, has anyone ever encounter something like this?  

    Thanks,

    ------------------------------
    HONGERA NGERAGEZA
    ------------------------------


  • 2.  RE: Bandwidth issue on QFX5100-48S-6Q and HP ProLiant DL380 Gen10 Servers.

    Posted 04-13-2022 17:17
    Hongera,

    Your performance issue could be created by flow-control, where the QFX5100 slows down due to receiving MAC pause frames from the server.  I was able to fix slow server performance in a Data Center with

    set interface xe-0/0/0 ether-options no-flow-control
    set interface xe-0/0/1 ether-options no-flow-control
    commit comment "disable flow-control for iperf testing"


    You can see if flow-control is enabled, and whether you have any MAC pause frames with "show interface extensive".  I would look at the interface stats before and after you make the change.

    Hope this helps.
    Tim Brown
    tim.brown at CopperRiverTech dot com

    ------------------------------
    TIM BROWN
    ------------------------------



  • 3.  RE: Bandwidth issue on QFX5100-48S-6Q and HP ProLiant DL380 Gen10 Servers.

    Posted 19 days ago
    Thanks for the contribution Tim, however I found the solution. I had to disable DCBX protocol that was enabled for all ports and the problem went away.

    delete protocols dcbx
    commit comment "disabling dcbx" and-quit


    ------------------------------
    HONGERA NGERAGEZA
    ------------------------------