L3 Devices Connection to FEX

[zekebashi]

Hello,

I was trying to find some Cisco documentations related to FEX best design guide but I couldn't find one that addresses my question. I found the below link and under the "Under the Guidelines and Limitations for the FEX" section, it mentions the limitations of using a FEX when connecting a L3 device, such as an ASA or Load Balancer, or another MLS.

My question is what is/are the design considerations to connect a L3 device to a FEX?

Thanks in advance, ~zK

[balaji.bandi · Accepted solution]

Generally FEX used for DC environment for Server Connectvity for L2 Only. - DC you can use Top of Rack, End of Rack so on ...for these FEX to save the cables and other advantage.

Suggestion as per the cisco was any L3 Device always use Nexus as Parent device, rather connecting to FEX (some case you can extend)

Since FEX are just dumb L2 switch module, do not process anything other than L2 Traffic, all the L3 traffic need to go to Nexus (Control Plane ) Parent and comeback.

I

[zekebashi]

Thanks for the info.

Much appreciated.

Best, ~zK