40 Gig to 4x10 Gig breakout

[S891]

Hello,

I am planning to use the module/optics QSFP-40G-SR4 (QSFP to Four SFP+ ) on the Nexus 9536 40G line card. 

I am assuming that there is no restriction on the 9536 line card as to how many ports and in which order can be setup for 40G to 4 x 10G breakout. Is there any limitation or restrction I shoudl be aware of?

My next question is to confirm the type of cable to be used for this. I see that Cisco has some cables available for this but their length is only up to 5m. I need approximately 25m to 30m. There are some third party options availabel for cables. One of them is this:

https://www.fs.com/products/40350.html?attribute=1726&id=96466

Does it look righ type of cable? Is there anything else required other than optics for 40G to 10G (QSFP-40G-SR4), 10G optics fro the other side (SFP-10G-SR) and the cable that I mentioned above?

Thanks

[Sergiu.Daniluk]

HI @S891 

I do not see any restrictions for X9536PQ linecards, however you should take a look yourself as well:

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/93x/interfaces/configuration/guide/b-cisco-nexus-9000-nx-os-interfaces-configuration-guide-93x/b-cisco-nexus-9000-nx-os-interfaces-configuration-guide-93x_chapter_010.html

Regarding the cable, what you shared in the link is an actual AOC breakout cable + SFPs. Basically it comes with the QSFP/SFPs and optical cable built-in. That's fine, however, the linecard does not support such a high length for this cable.

Reference: https://tmgmatrix.cisco.com/?npid=128

Better option is to use the QSFP-40G-SR4 & 4x 10GBASE-SR.

The 4x10G connectivity is achieved using an external 12-fiber parallel to 2-fiber duplex breakout cable, which connects the 40GBASE-SR4 module to four 10GBASE-SR optical interfaces. Cisco QSFP-40G-SR4 is optimized to guarantee interoperability with any IEEE 40GBASE-SR4 and in 4x10G mode with the 10GBASE-SR and SFP-10/25G-CSR (in10G mode).

Reference: https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/data_sheet_c78-660083.html

Stay safe,

Sergiu

[S891]

Hello Sergiu,

Thank you for your response. I think the module supports 100m with OM3. I found one reference in another post here. 

I am not sure whether the optics comes with cable. I did not see any Cisco part number for this module which supports more than 10m length.

I think I can just buy the 40GBASE-SR4 QSFP Module and 10G SFP from Cisco and purchase the cable from third party for 25m or 30m length. The link I posted for the third party in my original post (https://www.fs.com/products/40350.html?attribute=1726&id=96466) has these cables but I am not sure the cable comes with any optics or just the cable. I will have to find out. I need at least 25m length of fiber cable. 

"The Cisco 40GBASE-SR4 QSFP Modules support link lengths of 100 meters and 150 meters, respectively, on laser-optimized OM3 and OM4 multimode fibers. It primarily enables high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors. It can also be used in a 4x10G breakout mode for interoperability with 10GBASE-SR and SFP-10/25G-CSR-S (in 10G mode) interfaces up to 100 and 150 meters on OM3 and OM4 fibers, respectively."

Reference: https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/data_sheet_c78-660083.html

[Sergiu.Daniluk]

Hi @S891

QSFP-4X10G-AOC25M is not just a cable. It's an Active Optical Cable (AOC) with QSFP on one end and 4x SFPs on the other end. Because it has 25 meter length, is not supported by N9K-X9536PQ. Rule is simple - if is not on the list of compatibility matrix, it's not supported. https://tmgmatrix.cisco.com/?npid=128 Will it work? Maybe yes, maybe no. Do you get support if you experience any problems? Definitely no.

That's why I am saying that you can buy a QSFP-40G-SR4 + 4x 10GBASE-SR + a breakout fiber (similar with https://www.fs.com/de-en/products/42303.html of whatever length you need) and you are done.

Cheers,

Sergiu

[jaimgome]

Hi Sergiu, do we sell the breakout fiber jumpers you refer too?

Thank you,

Rick

[Sergiu.Daniluk]

Hi @jaimgome 

I do not know. I remember I have seen a lot of breakout fiber patches in the CALO lab (I am referring to the Brussels one), but I have no idea where they bought them from. Maybe you can check with the guys from CALO. I am sure they can guide you where to buy from.

Cheers,

Sergiu