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I have two machines, each with a 10 Gb adapter, directly connected with an SFP cable. I purchased three SFP cables that look exactly alike (physically and specs), but only one works. I'm having trouble finding clear information about SFP cables, so I appreciate the help in understanding the differences.

Here are the manfacturers, models, etc..

10 Gigabit Card #1: NetXen 3031

10 Gigabit Card #2: QLogic QLE3142-CU-CK

Cable #1 (the one that works) AIPC 7M

Cable #2 (no good) Blade Networks BN-SP-CBL-1M

Cable #3 (no good) Cisco SFP-H10GB-CU3M

I can't even get link lights with the two "no good" cables. I will be ordering a few more of the AIPC cables since they work of course, but I'd like to get a decent understanding of why one works, but not the other. Cable length? Active vs. passive? Different versions/revisions?

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Are the pinouts the same on all three cables? – Ben Quick Aug 5 '10 at 14:59
up vote 2 down vote accepted

After switching to Intel 10 GbE cards on both sides, the cable issues have disappeared! We also had trouble with overheating on those QLogic cards, so I recommend going with Intel.

We are using the Intel® 82599EB 10 Gigabit Ethernet Controller.

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I'm having a problem with a similar configuration, however I don't have another cable to test with.

The cards I'm using are both the same, Dell Part Numbers T645H, Intel Models 82598.

The cable I'm using between the cards is a Cisco SFP-H10GB-CU3M.

I found this information helpful from regarding which SFP+ cables will work with that card:

It mentions the cables have to comply with certain specifications to function properly, and according to the product page for the cable I have, they match and should be working.

Cisco cable details:

I saw this relatively cheap switch on eBay, (Item number: 370424159424) and considered buying that to see if it has to do with it not being a 'crossover' cable per se.

I'm hesitant to do that since the description mentions it having SFP ports, rather than SFP+ ports, and I'm unsure they're the same, or if they're compatible. This is my first foray into 10GB-land, and I'm early in the learning curve.

Does anyone have some good news for us on this?

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I've turned your URLs into links, but there's really two parts to your post - the first half is appropriate as an answer as it links to specs, but the 2nd half, asking about if the eBay product is appropriate, should really be a question on its own so that you can collect your own responses to it. Feel free to click the "Ask a Question" button in the top-right corner and re-post as a question. – Mark Henderson Aug 30 '10 at 6:26
OK, will do- thanks. – NginUS Aug 30 '10 at 9:09
I'm also going to be trying a 10Gb switch to see if it helps with the connection problems. I'll let you know how it goes. – Banjer Aug 30 '10 at 18:23
Banjer, have a look here at the question I posted, in case the answers may be relevant. aich_tee_tee_peah://‌​-cable-unplugged-although-cable-is-present – NginUS Aug 31 '10 at 2:31

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