Connecting FEX to Nexus 7K Parent switch

[dtran]

Hi all,

Hope everyone is doing well !!! I am looking into connecting the FEX to the N7K parent switch and have a couple questions. Thanks in advance for any inputs / suggestions.

I understand that FEX can be connected to its parent switch through a port channel and in my scenario I will have host systems that will be connected to the FEX that are on different VLANs. My question is do I need to set up the port channel in trunk mode to allow different VLANs passing through ? below is what I think the config would look like. Please verify the config below for me !!!

config t

interface port-channel 10

switchport mode fex-fabric

fex associate 110

switchport

switchport mode trunk

config t

interface e1/1

switchport mode fex-fabric

fex associate 110

channel-group 10

switchport

switchport mode trunk

config t

interface e1/2

switchport mode fex-fabric

fex associate 110

channel-group 10

switchport

switchport mode trunk

[Marwan ALshawi · Accepted solution]

Hi

Because the Nexus 2000 fabric extender acts as a remote line card to the parent switch, all the configuration takes place on the parent Switch, the N7K in your case

for fabric extender interfaces they have to be in fex-fabric mode this not normal L2 etherchannel it is fabric expansion

example:

(config)#

fex 100

(config-fex)#

pinning max-links 1

switch# configure terminal

switch(config)# interface port-channel 4

switch(config-if)# switchport mode fex-fabric

switch(config-if)# fex associate 100

switch(config-if)# exit

switch(config)# interface ethernet 1/37

switch(config-if)# switchport mode fex-fabric

switch(config-if)# fex associate 100

switch(config-if)# channel-group 4

switch(config)# interface ethernet 1/38

switch(config-if)# switchport mode fex-fabric

switch(config-if)#  fex associate 100

switch(config-if)#  channel-group 4

A fabric interface includes the corresponding interface on the parent switch. This interface is enabled when you enter the switchport mode fex-fabric command.

HTH

if helpful Rate

[dtran]

Hi Marwan !! Thanks for your help !!!

I understand the N2K acts as a remote line card to the parent switch, so all vlans is allowed through the port channel correct ? do I need the "switchport" and the "switchport mode trunk" commands ?

Thanks again !!

Danny

[Marwan ALshawi]

No, the mode is fex

Sent from Cisco Technical Support iPhone App

[dtran]

Got it,

So by default all VLANs are allowed through the port channel ? Do I need the "switchport" command ?

Thanks Marwan !!!

D.

[Marwan ALshawi]

For the FEX ports just use the commands in the example above

Once the FEX get discovered and associated in the parent switch you will see ports like 100/x/x. There you can configure vpc, trunk ..etc

HTH

Sent from Cisco Technical Support iPhone App

[dtran]

Thanks Marwan !!! I will give it a shot !!! I appreciate all your help !!!

D>

[Marwan ALshawi]

Hi

thanks for the nice rating

and just for your reference use the bellow config guide

Configuring the Fabric Extender with Nexus 7000

http://www.cisco.com/en/US/docs/switches/datacenter/sw/5_x/nx-os/interfaces/Configuring_the_Cisco_Nexus_2000_Series_Fabric_Extender_chapter1.html#con_1195285

HTH