MS stack and MX

nst1
Building a reputation

MS stack and MX

 

 

Currently I have two MS (in stack) and an MX I want to connect a second cable from the second MS is this possible?? because I already tried it and the network becomes unstable, that is, I start losing packets.

 

Diagrama.PNG

3 Replies 3
Brash
Kind of a big deal
Kind of a big deal

With the MS in a stack, they are essentially a single switch.
When you connect a second cable to the MX, you're inadvertently causing a loop in the network as you have 2 connections between the devices.

Because the MX does not run spanning-tree, it will pass BPDU's through between the two links. In theory, spanning-tree should detect this loop and disable (AKA spanning-tree block) one of the links.

Have a look at the following thread for more info.

Solved: more uplink from MS switch stack to MX firewall make switches unavailiable - The Meraki Comm...

alemabrahao
Kind of a big deal
Kind of a big deal

I have 2 pairs of MX with several ports connected in a pair of stacked switches and it has been working without any problem.

 

LACP & Link Aggregation
The MX does not run LACP or any link aggregation protocols. Connecting aggregated ports to the LAN of the MX is not supported; all connected ports should be un-aggregated. If multiple ports are connected to the MX from a single switch for redundancy, it is highly recommended that you run STP on that switch, to ensure that one of the redundant ports is safely put into a blocking state.

 

alemabrahao_0-1668086113789.png

 

I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.

Please, if this post was useful, leave your kudos and mark it as solved.
KarstenI
Kind of a big deal
Kind of a big deal

Here is a blog-post that explains a little bit about this problem:

https://cyber-fi.net/index.php/2022/03/13/how-to-connect-the-meraki-mx-to-ms-switches/

Get notified when there are additional replies to this discussion.
Welcome to the Meraki Community!
To start contributing, simply sign in with your Cisco account. If you don't yet have a Cisco account, you can sign up.
Labels