I have a quick question for you 40GbE gurus out there.
I just picked up two connectx-3 cards and wanted to link the two up directly about 15M apart (in a separate room)
Are those MPO cables that seem to cost a gazillion dollars per meter (combined with surprisingly cheap QSFP+ transceivers) my only option? I saw a cisco transceiver for 40G over a single LC fiber but it was prohibitively expensive, the opposite problem of former... Active optical 40GbE cables designed for QSFP+ and 40GbE also seem sort of expensive.
Everybody I've talked to say that the old "
regular qsfp" (not QSFP+) gear designed for 40G infiniband will not work for 40GbE (active cables included).
I asked mellanox support regarding one active "regular qsfp" "infiniband" cable I saw on ebay:
Thank you for contacting Mellanox Technical Support.
Please note that MC2206310-015 is an Infiniband only cable (Mellanox® active fiber cable, IB QDR/FDR10, 40Gb/s, QSFP, 15m) . And cannot be used in ethernet.
If you would like to receive recommendation for Ethernet cables we can redirect this case to our sales department which can provide you with best cables for your needs
Please let us know if there is anything else we can assist with.
We are looking forward to hearing from you.
Are they telling the truth or do they just want me to buy more expensive cables? How is it that 40Gb Ethernet and infiniband would require different cables despite having similar transfer rates?
What do you smart folk here think I should do? Give up on 40GbE and run sfp+ adapters over LC fiber at 10Gb?