Multi-gigabit and 10G SFP+

[parker.c]

Hello,

So this could be a dumb question....

Looking at the 3850 24UX as a possible device to be used for a small site server and storage solution. The storage and servers are SFP+. Initially my thought was a 3850-12XS with 3M twinax. However since there is no need for fiber, and having multi gig and greater port density would allow me to use these switches for a greater range of devices, the 24UX seems interesting. However I want to be certain there will be no issues going from a 10G SFP+ (SFP10G-T) via cat6e (less than 3M) to a multigigabit port.

Maybe this is a no brainier and 10G ether is 10G ether. But in my experience ... never hurts to ask.

Thanks!

[Scott Hodgdon · Accepted solution]

Parker,

The 10Gbps RJ-45 interface of an mGig is just traditional IEEE standards-based 10Gbps. You should have no problem connecting over Cat6a (have not seen reference to Cat6e in https://www.cisco.com/c/dam/en/us/solutions/collateral/enterprise-networks/catalyst-multigigabit-switching/nb-06-mgig-faq-cte-en.pdf , but I don't see why it wouldn't work).

As an aside, why choose a Cat 3850 mGig switch instead of a Cat 9300 mGig switch ?

Cheers,

Scott Hodgdon

Senior Technical Marketing Engineer

Enterprise Networking Group

[parker.c]

Scott,

Thanks! Choice of the 3K over 9K is mostly familiarity (save multi gig :-) ) with the product and possibly price. Though truth be told haven't priced the 9K out yet.

I keep expecting 3850 to get a EoS date. Since that hasn't happened it still seems viable. But I recognize given 3K's age the 9K is going to be a better long term choice.

Chris

[Leo Laohoo]

Make sure you test your QoS properly.
QoS is mandatory for 3650/3850 and is very unforgiving.

[Joseph W. Doherty]

"However I want to be certain there will be no issues going from a 10G SFP+ (SFP10G-T) via cat6e (less than 3M) to a multigigabit port."

There can be issues, as a mGig port might not have the hardware resources to support it like a dedicated SFP+ port. (BTW, not all switch series SFP+ ports are guaranteed to have the same hardware resources supporting them either. I.e. the bandiwdth of port doesn't guarantee how it will perform, which can be critically important when working with storage devices.)