Two EXOS stack and MLAG betwen them

[Peter_Majercak]

Hi guys, i have a question if it is possible to create this design.
I would like to have 2 stacks. Each stack consist from 3x 5520 24x. Nodes of each stack are conected via QSFP28 ports. Each stack member is fitted by VIM4Y module. I is possible to create MLAG connection between these two stack via VIM4Y ports?

Many thanks for your advice.

[Fredrik_Jansson]

Hi,
I came across your post about using MLAG between two EXOS stacks. 

Did you ever implement something like that or did you find an answer why is was not possible or not a good idea?

I found this guide...
https://extreme-networks.my.site.com/ExtrArticleDetail?an=000082635

But I feel complexity might rise quite fast in a small network... 

BR
Fredrik

[Stefan_K_]

Hi @Fredrik_Jansson 

Why shouldn't it work? 🙂

MLAG is great and the complexity isn't that much higher. You will have to use VRRP if the switches are routing in your network and you have to execute the commands on two switches instead of one, but orchestration mode can be used, to reflect the issued commands on the MLAG peer.

[StephenW]

Hi Peter,

The 5520's are capable of stacking at V160 with QSFP+ ports U1-Port 24 and U2-port 25.  If you have a 5520-VIM-4X You can stack at V80.  You could use the VIM4Y for the MLAG ISC, but not for stacking.

Hope this helps!

Refrence links:

Available Stacking Methods

Native and Alternate Stacking Ports

--Stephen

[StephenW]

Hi Peter,

A new update.  The 5520's will support V200 Stacking in 31.6 with QSFP28 cable on ports U1 and U2 but not on the VIM4Y.

--Stephen