ACI Spine/Leaf cables

[David Ashley]

Hi all,

We are about to start the implementation of an ACI infrastructure for a customer.  The spine, leaf switches will each have 100GbE transceivers, QSFP-100G-SR4-S.  Can anyone advise on the cables required to connect the spines and leafs together?

Many thanks,

[Tomas de Leon]

Please take a look at the following links and make sure to look for the ACI versions:

Cisco 100-Gigabit Transceiver Modules Compatibility Matrix
http://www.cisco.com/c/en/us/td/docs/interfaces_modules/transceiver_modules/compatibility/matrix/100GE_Tx_Matrix.html

Cisco Nexus 9000 Series (Fixed 9300)
http://www.cisco.com/c/en/us/td/docs/interfaces_modules/transceiver_modules/compatibility/matrix/100GE_Tx_Matrix.html#_Toc451495202

Cisco Nexus 9000 Series (Modular 9500)
http://www.cisco.com/c/en/us/td/docs/interfaces_modules/transceiver_modules/compatibility/matrix/100GE_Tx_Matrix.html#_Toc451495201

Cisco 100GBASE QSFP-100G Modules
http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/datasheet-c78-736282.pdf

If this answers your questions or resolves your issue, we would appreciate if you would rate the provided response and mark your questions answered. What this does is let other viewers know that an appropriate resolution or answer has been given to the question that was posted. This helps other users that may have experienced the similar issue.

Thanks again for using the Cisco Support Community for ACI!

T.

[David Ashley]

Hi Tomas,

Many thanks for the response; however, unless I'm missing it, these links don't mention the cables needed?  MPO cables, as far as I know, can be specified differently at the time of ordering in terms of the number of cores within the cable (in this case 12), and if they need to be cross, rollover or straight through cables.  Are you able to confirm this, along with the pin outs?  We need to get this right as it's going to be around £10k worth of cables alone for this project,

Thanks,

[Tomas de Leon]

The cables are part of the cisco part# shown here in the attachments:

simply verify with your Cisco Sales Account Representative prior to ordering.  Also if you google the listed partnumbers for your Nexus 9000 model for ACI. You will also see approved versions online also.  They are include the cables base on the distance you order.

I hope this helps!

T.

[David Ashley]

Hi Tomas,

These are twinax cables.  They have QSFP transceivers, QSFP-100G-SR4-S, we need the correct cables to plug into the transceivers.

Thanks,

[Tomas de Leon]

12 Fiber Multimode (OM4) MPO Fiber Cable with MPO connectors. 

From the datasheet link:

The Cisco 100GBASE-SR4-S QSFP Module supports link lengths of up to 70m (100m) over OM3 (OM4) Multimode Fiber with MPO connectors.  It primarily enables high-bandwidth 100G optical links over 12-fiber parallel fiber terminated with MPO multifiber connectors.

[David Ashley]

Thanks Tomas.  Could you advise on the below?

What is meant by "12-fiber parallel fiber terminated with MPO multifiber connectors"?  Does that mean straight cable pins? 1 to 12, 2 to 11 etc?  Attached are a couple of pictures also.

Thanks,

[adrabkin]

Did you ever get the answer to your question? I have a similar problem. I'm not using any cassettes or patch panels, just going from switch to switch.

There is no documentation on polarity on Cisco's website!

Thanks!

[kunukg]

Same here.

[baanderson]

Speaking from experience. Somewhere in your cable runs the fibers have to flip 1-12, 2-11, ect. as the QSFP transceivers have the send and receive emitters in the same locations. The product we found to work best was made by Panduit because it gave the flexibility to have a cable be straight through or flip, and male or female depending on how the cable was being used example being from switch to switch or switch to switch through a bulkhead connector. This is a link to a data sheet about the Panduit product that i am referring to https://www.panduit.com/content/dam/panduit/en/landing-pages/QkNetPanMPOTkCable.pdf 

If you are knowledgeable of male/female connections and fiber polarity A and B for MPO then you should have no problems with planning your layout and then ordering the specific cables you need for each run instead of buying the more universal style that I link to above. Just keep in mind that somewhere the fiber layout must swap between devices so that send is going to receive.