SFP with Nexus 5500/2000

[hanwucisco]

We ordered two 5548P and several 2000. They came with two types of SFPs. One is SFP-10G-SR, the other FET-10G.

What is FET-10G used for? between 2000 FEX and computer servers?

thanks,

Han

[Jeremy Waldrop]

Yes, FET are for FEX (Nexus 2k) uplinks. You must use FET on both ends of the connection. FET are lower-power, lower-cost than 10G-SRs. You can also use 10G-SRs or Twinax to connect FEX but FETs come with nexus 2k.

[hanwucisco]

I tried to use FET from 2K to 5K. it showed invalid sfp plug on the 5K(with FET to 10g-SR and FET to FET)? so I had to change to 10g. anything i did wrong?

[Lucien Avramov]

You need to use FET on N5K side and FET on N2K (match the same optic

type). The speed is 10GE for them.

[Jeremy Waldrop]

It will show invalid SFP until you enable the fex feature and configure the interfaces/port-channel as fex fabric. You have to use the same on both ends, either FET or 10G-SR.

example

feature fex

interface port-channel101

  description Port channel, vPC 101 to FEX 101 Nexus 2248

  switchport mode fex-fabric

  fex associate 101

  vpc 101

interface Ethernet1/32

  description Connection to FEX 101 Nexus 2248 Fabric port 1/1

  switchport mode fex-fabric

  fex associate 101

  channel-group 101

[Devavrat Oka]

Use this compatibility matrix.

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps10110/data_sheet_c78-507093.html

[hlwanmoetun85]

I have the same problem and i did port mode fex. Then the FET is not showing invalid anymore.

But how about my SFP-10G-SR. Where should I use?