SPAN FEX Uplink

[kishore.rajani]

Hi, 

I have a Nexus 6K - 2K fex setup. The FEXs are dual connected to the N6Ks. I have been tasked to SPAN all traffic on this set-up. The number of VLANs are more than 32, so I cant use VLANs as source. 

Also the total number of connected ports (incl FEX ports) are more than 128. 

Hence I wanted to get your advise if we can use the N6K ports, to which the FEX connect, as the source ports or is there any limitation that we cant use FEX Uplinks as source?

Appreciate if you can advise.

[Mark Malone]

Hi
first thing be very careful running SPAN on a NX switch its not like IOS , can easily take the network down , start small dont turn it all on at once

FYI
Beginning with Cisco NX-OS Release 5.2, the Cisco Nexus 2000 Series Fabric Extender interfaces and the fabric port channels connected to the Cisco Nexus 2000 Series Fabric Extender can be configured as SPAN sources. However, they cannot be configured as SPAN destinations.

[kishore.rajani]

Hi Mark,

What I'm after is mirroring the 6k ports where the fex connect. That would save me from listing each connected port on fex as monitor source.

I couldn't find that in the Cisco documentation, in source ports characteristics.

[Mark Malone]

Hi
see Rezas post here , its not allowed

i dont see the option available on my 9/5s or 7k sets either
https://community.cisco.com/t5/server-networking/is-span-port-not-allowed-in-nexus-fex-port/td-p/2351197

[kishore.rajani]

Hi Mark,

That post is referring to FEX port as SPAN destination - which I am aware - we cant use fex port as SPAN destination.

I have 2K fex connecting to  Nexus 6k  on eth1/12. So all i want to know is can eth1/12 be configured as SPAN source.