Beware of EMC switches sold as Mellanox SX6XXX on eBay

Discussion in 'Networking' started by mpogr, Aug 2, 2016.

  1. oxynazin

    oxynazin New Member

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    But CX3 supports RoCE according to their product brief pdf. Unclear v1 or v2, but somewhere I saw that CX2 - RoCEv1, CX3 - RoCEv2.
     
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  2. mpogr

    mpogr Active Member

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    Yes, I meant RoCE, and, indeed, CX-3 supports v1, but only CX-3 Pro and up support v2, which is quite a bit of a difference latency-wise.
    I have done some measurements with my setup using SRP a while ago, now need to redo the same baseline to see how things are different with iSER, but, from memory, there was quite a bit of performance loss, especially with multithreaded workloads.
     
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  3. oxynazin

    oxynazin New Member

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    Found this huge article: https://www.demartek.com/Reports_Free/Demartek_IBTA_RoCE_Deployment_Guide_2018-07.pdf Have not read all article, because there're too many new information for me. But found some interesting parts. For SMB Direct there's intersting part: "If RoCE v2 is not necessary for routing purposes, RoCE v1 may give better performance.". And in the end: "The addition of ETS and RoCEv2 Congestion Management resulted in improved RoCE throughput and decreased latency.". As I understood, v2 adds some overhead for Layer3 support but also adds "RoCEv2 Congestion Management (RCM)". So v1 must be at least as fast as v2, until you not utilize network for 100%. Am I right?
     
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  4. zxv

    zxv Velcro - What a rip off!

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    #224
  5. manfri

    manfri New Member

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    Kudos to mpogr for the guide... great work... but a bit extreme for my heart, and tooo much effort for my needs...
    I'm gonna pass :cool:))
     
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  6. Tim111

    Tim111 New Member

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    Just signed up, is there a way I can get information for flashing EMC sx6012 please.
     
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  7. Terry Wallace

    Terry Wallace Member

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    If you start at page 1 of this thread and read through it just about all the information has been presented here. :)
    Good luck on conversion.
    Post when you get stuck on a specific step and we'll walk you through it.
     
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  8. Tim111

    Tim111 New Member

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    Thanks Terry.
     
    #228
  9. zxv

    zxv Velcro - What a rip off!

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    #229
  10. i386

    i386 Well-Known Member

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    #230
  11. Rand__

    Rand__ Well-Known Member

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  12. Freebsd1976

    Freebsd1976 Member

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    an off-topic question , howto connect sx6012 to internet?
    my sx6012 only for spark cluster in my home lab, no internet access,.
    now for system update which need internet access,I consider connect it to other switch for internet access, my other switch have rj45 1G port, but the question is how to connect two switch , sx6012 only the management port is rj45?
     
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  13. i386

    i386 Well-Known Member

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    You could use a qsfp to sfp Adapter and a rj45 sfp Module
     
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  14. Freebsd1976

    Freebsd1976 Member

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    thanks a lot ,I found the other switch has one 10g port, so I think I can buy one qsfp+ to four sfp fan out cable uplink for internet access
     
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  15. Freebsd1976

    Freebsd1976 Member

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    Another question , I know we could not upgrade os ,but could we upgrade the firmware, anyone try this.
     
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  16. Freebsd1976

    Freebsd1976 Member

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    thank a lot , this is want I want. Btw how to do make this output fixed 5v ?the default output seems adjustable .

    PS : find howto fix output ,
    5PCS Mini DC to DC Adjustable Step Down Module 12/24V to 5V 3A Buck Converter Power Supply Module
    There is a YouTube video demo howto do this
     
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    Last edited: Jan 17, 2019 at 10:16 PM
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