2 Replies Latest reply on May 10, 2018 7:49 AM by halr

    Mixing infiniband versions

    wpoely86

      Can you mix different versions of infiniband in the same network?

       

      We have a setup using QDR (connectx, connectx3 and connectx4 with a voltaire 4036 toplevel switch). We're looking to buy a new enclosure with EDR and I was wondering how we can integrate both of them. Can we simply connect the EDR switch in the enclosure into our current QDR toplevel switch? And what does the mean for the speed? Will the EDR blade be able to talk EDR to each other or will everything scale down to QDR?

       

      Maybe I'm not looking hard enough but I don't seem to be able to find any documentation on this?

        • Re: Mixing infiniband versions
          halr

          In terms of the IBA spec, it is optional as to what link speeds are supported (other than SDR). You can tell by smpquery portinfo for one of the switch external/physical ports.

           

          If you are talking about Mellanox EDR switch, it supports QDR as well as some other speeds (like FDR and FDR10).

            • Re: Mixing infiniband versions
              halr

              EDR capable <-> QDR capable link should come up at QDR.

              EDR capable <-> EDR capable link should come up at EDR.

              If EDR node talks to other EDR node across all EDR links, rate will be 100 Gbps (4x EDR).

              When EDR node talks to QDR node, rate will be 40 Gbps (4x QDR).

              When EDR node talks to other EDR node with intervening QDR link on path, rate will also be 40 Gbps.