Single FEX suffice?

[Pete Lanzone]

Hello -

pardon some of the ignorance but I am just trying to do a sanity check.

I am setting up a 5108 UCS chassis with (2) 6240 Fabric Interconnects that will connect to a single 2232PP 10g FEX. The FEX is uplinked to (2) 5596 switches (2links) connected to each 5596 for a total of 4 links. Again this is for a lab environment. I don't think this would be best practice as the single point fo failure is the FEX however will I be fine in this scenario for what I need to do or is it required that I need (2) FEX. (trying to mitiggate costs for this project) 

[padramas]

Hello Pete,

If you configure active / active FEX, you can attach single FEX to both N5K and then connect FI to FEX.

http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/adapter-fex/521n11/b_5k_Adapter_FEX_Config_521N11_chapter_010.html

NOTE :- You do not need to adapter FEx, this is my first search hit  doc :-)

Padma

[Pete Lanzone]

Thanks for the reply.

So it appears there essentially nothing for me to do? the Single FEX should be fine for my implementation that I outlined?

Sorry just a bit confused or I am over thinking it..

[padramas]

Single FEX would meet your requirements.

[Pete Lanzone]

Ok thanks. I just wanted to make sure becuase I thought each FEX goes to its own interconnect. (well it should) but I will assume that is for redundency purposes as I already covered in the earlier post. But putting two Fabric Interconnects on a single FEX shoudl still work just no redundancy.

Correct? Anything else I am missing (besides second FEX) or need to do to have two fabric interconnects connect to one FEX?

[padramas]

Hello,

When FEX is owned by FI, each FEX can be connected to single FI only. In your scenario, N5K is the parent switch for your FEX.

Apart from issues like redundancy, oversubscription ( depending upon the traffic load ), FI will operate fine when they are connected to single FEX.

Padma