Does Nexus 2148 Fex support server static Etherchannels and/or LACP

Unanswered Question
Aug 18th, 2010

Running n5000-uk9.4.2.1.N1.1.bin so:

Does Nexus 2148 Fex support static Etherchannels and/or LACP to say a server (such as VM or storage servers). I will run the FEX 2148 to a single nexus 5010


I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Yudong Wu Wed, 08/18/2010 - 10:33

In layer 2 features of data sheet, it says,

• PortChannel on server ports (Cisco Nexus 2200 Series only)

So, I think it might not supported on 21xx

Atif Awan Wed, 08/18/2010 - 11:05

Yes that is correct. Etherchannel on host ports on a 2148 is not supported. You can have a two member port vPC from a server but that will require each member port to be on a different FEX and the FEX need to be single attached, one to each N5K.

aamercado Thu, 08/19/2010 - 08:42

Various CCO docs is confusing - Per the latest doc dated March 2010 which is the design guide below PDF page 29-30,32, I plan to set up "Host PortChannels" from Server to FEX2148 (per Page 32) with a "straight-through" topology VPC so not using "Active-Active" topology. This corresponds to your last reply

Page 39 states below:

"Dual-connected servers that require PortChannels must be connected to fabric extenders single-homed with two or more ports in the PortChannel and half of the ports attached to each fabric extender"

while Page 47 Figure 33 shows an example using more than 2 port to each N5k for a total of 4 ports in the "host portchannel" – note that this whole design guide uses the 2148 in most examples configs. However, there is reference to the FEX2248 and FEX2232 but these appear to be limited in sample configs in this doc…so my question is – does the FEX 2148 support more than 2 ports for “host portchannels” I want to use a total of 4 in my server portchannel so 2 to say FEX2148#A and 2 to FEX2148#B

to also reconfirm - the above link page 54 and below link Page 13 of design guide below section “Teaming on the Server” implies support for both “Static port channeling “ and “IEEE 802.3ad port channeling:

so can I assume for the FEX2148,  I can use more than 2 ports in a “host port channel” for either Static or 802.3ad (which I assume is LACP).


Atif Awan Thu, 08/19/2010 - 09:41

I have not read the complete document but after skimming through it I do not believe it should generate any confusion. The answer is still the same, with 2148 you have the following options:

  • With FEX in straight through mode you can have up to two ports in a vPC per server with each port terminating on a different FEX. I believe you can have both LACP and static port channeling in this case.
  • With FEX in Active/Active topology you cannot have host vPC. You can, however, run the servers in Active/Standby or TLB (Transmit Load Balancing) configurations.
  • If you want to have four ports in a portchannel with 2148 the only option I can think of is to have two separate port-channels (vPCs).

Kindly refer to Figures 21 to 24 of the same document you mentioned in your previous reply as these explicitly tell you what your options are with 2248/2232 and 2148. I hope it is clear now.



This Discussion