Multipod questions infra vlan and versioning

[mmacdonald70]

I'm testing out multipod and I have two questions that I'm having trouble finding answers for in the documentation:

1.  Everything that I read says that the access port on the IPN Must use vlan 4.  If An ACI was set to use a different vlan for the infra vlan, should we be using this or vlan 4?

2.  I understand that Multipod is only supported on v2.x.  If the hardware in pod2 is using a lower version, does it need to be upgraded before it can join?  Or would it be able join and then be upgraded?  If it matters, the spines are 9504.

[Tomas de Leon · Accepted solution]

Yes, The connection between the spines and the IPN gateway must use VLAN 4.  This is something firmware & hardware coded on the SPINE. The IPN end has to be configured with Vlan 4.

In regards to firmware versions, the APICs need to be all at the same version.  The switches may be at a different version to join the fabric, but will need to be upgraded once the fabric is fully fit.  Just make sure the fabric firmware policy is set to allow "ANY" versions to join the fabric.

Thank you for participating in the Cisco Support Forum for ACI! If you have other questions related to this post, please let us know. If this response answers your questions, please mark this post "answered" and assign a rating to the response(s) provided. This will help notify other viewers that your question(s) is answered and this helps us provide better responses for this and future questions.

Thank you!

T.

[mmacdonald70]

Thanks.  I verified the fabric policy but it still wasn't working.  After I manually upgraded the Pod-2 Spine from 1.2.3c to 2.1.1h, it showed up in the APIC.

[robertke1]

Hi Tomas,

You mentioned that vlan 4 (actually it is a subinterface with tag 4) is a must for multipod connection between IPN and Spine. The second part of the question was what if the infra vlan for the fabric is not the default (4). If we choose vlan 2000 as infra vlan, do we still need vlan 4 (subinterface with tag 4) for multipod connection?

The second question: Can we do 2 multi-pod connections from one spine to two IPNs (the customer has just one spine per pod and 2 dwdm links between?

Thanks for clarifying.

Cheers,

Robert

[Tomas de Leon]

Robert,

Vlan4 is hardcoded on the spines for it's connection to the "IPN Network".  This does not change. 

If you have different PODs connected to the "IPN Network", each POD still requires it's own TEP Address Pool. The infra-vlan is the same throughout the entire fabric.

There is a single "IPN Network" for all Pods in a Single Fabric.

I hope this helps

T.

[robertke1]

Hi Tomas,

Thanks for explanation. I think my question was not clear enough, so I am enclosing a simple drawing what I had in mind. My question was if I can use two p2p links from single spine to 2 IPN devices which are connected to 2 IPN devices in PoD-2. My only concern is that both links include vlan 4, but since subinterfaces are used, this should not be in issue.

Thanks,

Robert