Nexus 2000 Etherchannel Limits

[daveo]

We recentely ran into a limit on number of links allowed for devices connected to nexus 2k. Currently there is only support for (1) 1GB link to Each of the 2 Nexus 2k. See Below.

The question i have is if this is a hardware limitation or a software limitation and if there is any insight on future support for higher capacity etherchannels.

From Config Guide

The current generation of Cisco Nexus 2000 Series Fabric Extender does not support EtherChannels on its host interfaces. Therefore a maximum of two links can be configured in an EtherChannel from the server where each link is connected to a separate Fabric Extender.

http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/configuration/nxos/Cisco_Nexus_5000_Series_NX-OS_Software_Configuration_Guide_chapter11.html

Thanks in advance

DaveO

[allan.thomas]

This will almost certainly be attributed to hardware, the reason I say that is that ordinarily FEX to N5K connectivity can only support upto 16 Port-Channel hardware resources, and as the 5K can only support upto 12 FEXs, then at least 12 hardware Port-Channels are required if these are dual-connected, this is not including any vPC peer-link, and/or Port-Channels to the Core or Distribution.  Therefore, you can see the limitations, hence EtherChannels on host ports is not supported.

However, I have discussed this with Cisco when I first came across this, and apparently I have been led to believe that the FEX 2248T will provide support for upto 8 host-ports in port-channel, which was on the road-map for around the 2nd quarter this year.  Whether this has changed I could not honestly say.

Hope this helps

Allan.

[daveo]

Allan,

Thanks for the response.

I was leaning toward the hardware side, but this does help provide direction.

We were able to design a workaround by creating 2 seperate port channels by creating a 2nd v2witch each with 2 links and splitting the connections within the ESX host.

Thanks again

DaveO

[Carlo Schmidt]

This is a N2148 limitation. N22XX fexes allow up to 8 links per fex. Please reference this guide for updated information.

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/C07-572829-01_Design_N5K_N2K_vPC_DG.pdf

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