etherchannel in multihomed nx 2148?

[tiwang]

Hi out there

I have setup a pair of nx5020 with a single "multihomed" nx2148 from where I wan't to add a number of 1Gig ports in a etherchannel to a cat 3750 - but I cannot get the etherchannel up - it claims that i cannot do this on a multichassis switch - can some out there guide me to a sample?

best regards /i

[Atif Awan]

So you are taking the risk with the etherchannel design :-). It is better you do the change during a maintenance window as you will need to make the change on both N5Ks (vPC scenario). I believe there will be traffic disruption but if you plan it correctly you can minimize the disruption.

Atif

[tiwang]

hi again

I am forced to do this because we need the redundance we get - and of course also wan't the benefits from the loadbalancing - from the design in chads post - hereby can I also update the nexus one by one without risc - but I am a bit in doubt how to define the ports on the 3750 - how should these be defined when they are the opposite of a host-mode etherchannel from the nexus ?

best regards /ti

[Atif Awan · Accepted solution]

tiwang wrote:
hi again
I am forced to do this because we need the redundance we get - and of course also wan't the benefits from the loadbalancing - from the design in chads post - hereby can I also update the nexus one by one without risc - but I am a bit in doubt how to define the ports on the 3750 - how should these be defined when they are the opposite of a host-mode etherchannel from the nexus ?
best regards /ti

Etherchannel from 3750 will be a standard LACP etherchannel (channel-protocol lacp / channel-group X mode active). From 3750s perspective the two N5Ks (via N2k) will appear as one logical switch. Please test this first before trying out in production.

Atif

[ppalmerjr]

This is very similar to a scenario I have. (Sorry for the horrible drawing below) I'm under the impression that I should be able to connect in the fashion below with VPC's made on the N5K side and a regular etherchannel configured on the catalyst side.  When I mocked it up quickly in the lab I found that the Po on the Cat side went active but one member went into the "suspended" state.  On the N5K side the channel went with one member in the (H)ot Standby state.  Should I be able to get both members of this Po into a "P" state?

Cat4900  ----------  Cat4900

   |  vpc1\               / vpc2 |

   |          \           /          |

   |             \      /            |

   |               \  /              |

   |              /  \               |

   |          /         \            |

   |       /              \          |

N5K-1 ----vPC------ N5K-2

Thanks!