[c-nsp] Nexus FEXs and pinning max-links

[-Hammer-]

All,
     I've been playing with some Nexus gear in our lab and I'm confused 
on a physical layer issue. When defining the FEX, you define the 
max-links. Originally I set it to four and then built my port channel. 
Of course, it gave me an error

ERROR: FEX max-links not configured to be one

Which after googling and thinking thru makes sense. I'm defining the 
ports as a port channel so I need a max-links of "one". Not "four" (as 
in four wires between the N5K and N2K). That makes sense. What I'm 
struggling with is in what scenario I would NOT create a port channel. 
When would I just assign the physical links to the FEX and not build an 
etherchannel for them? Anyone?


!!!get your FEX on

!!!! define a FEX

fex 101
     desc FEX101
     !!! define maximum links!
     !!! trick question! If the link is a PO then your max links is 1.
     pinning max-links 1

!!!! define the port channel
interf po101
     !!! MODE!
     switch mod fex-fabric
     !!! associate it with the logical FEX
     fex asso 101

!!!! Bring the physicals (with the FETs connected) into the PO101
interf ra e2/1 - 4
     !!! MODE!
     switch mode fex-fabric
     !!! call the fex!
     fex ass 101
     !!! call the PO
     channel-group 101
     no shut


-- 


-Hammer-

"I was a normal American nerd"
-Jack Herer