LACP/LAG with 'switches in between' (not true 2-Tier)?

[Frank]

I'm drawing a blank as to "do I do this right, or what do I do wrong?". If you look at the following:

Note that there is no ISC/MLAG between the two 460s.

Coworker and I are debating if the two ports on the Cisco stack need to be put in a LACP/channel-group or not. Neither of us has good enough arguments or detailed enough knowledge as to what exactly is happening, so if anyone could help, that'd be awesome!

- Is the above design reasonable/unreasonable/plain wrong?
- Do the Cisco ports need to be configured as two regular normal trunked/tagged ports, or do they need to be configured as channel/lacp/shared ports?
- or would they only need to be lacp ports if (and only if) the 460s would get an ISC/MLAG between them?

At this point I'm not sure if I could be trusted to connect two tin cans with a string!

Thanks for you help,

Frank

[Frank]

Sadly, the Cisco stack belongs to the customer, and my boss just ran out of SummitStacks to hand out for free. I'm just glad it's not a $50 D-Link 😄

[cbuchenau]

How about replacing the Cisco Stack with a Summit Stack, and then you run a nice EAPS ring? 🙂

[cbuchenau]

Interesting...

Is connecting the Cisco stack directly to the 2 BD chassis not an option? Then you configure a LAG on the Cisco stack and MLAG on the 2 BDs (as already done).

Otherwise, consider a 2-tier-MLAG design. In which case you need another ISC between the 2 460. See this GTAC KB article:
https://gtacknowledge.extremenetworks.com/articles/How_To/Sample-configuration-for-two-tier-MLAG/?q=...
Replace the Server in the diagram with your Cisco stack...

[Frank]

Distances/cabling would make connecting the stack to the BDs - ahem - "challenging".

[Paul_Russo]

Hey Frank

Can I ask why not do MLAG between the two 460s? I think the two tier design is a better way to go as it provides added bandwidth and redundancy.

How would you handle Cisco port failover in the above design?

P