MS390 stacking difference to other MS series

[PowerStacking]

Hello,

I plan to deploy Meraki MS switches in a building, where we plan to build stacks for each floor.

One floor should be based on 2x MS390 switches which will be stacked.

All other floors should be based on 2x MS225 switches per floor which also will be stacked.

We have experience regarding MS225 stacking, but it's our first time to stack MS390 switches.

After some research we discovered following note from Cisco:

MS switches other than the MS390 have one active switch in the stack and all other switches are member switches. MS390 stacks also have one standby switch. The standby becomes the active unit in the event of a failure of that switch.

Source: https://documentation.meraki.com/MS/Stacking/Switch_Stacks

Could someone further explain what this description means?

Is the 2nd MS390 member fully in standby and not able to send data?

Thanks a lot and best regards

[alemabrahao]

For example, if you have Interfaces vlans, routes configured in the MS master, in case of failure with the Master the Standbay will "take over" the configurations and starts to process all the information.

In a stack containing multiple switches, you can configure master/slave switchover to enable the original standby switch to become the new master switch to implement backup between master and standby switches.

Context

In a stack containing multiple switches, you can manually switch the master and standby switches during software upgrade or system maintenance. After the master/slave switchover is complete, the original master switch joins the stack after restarting, and the original switch becomes the new master switch.

[PowerStacking]

Appreciate the quick reply!

If I understand correctly, the MS390 has an additional stack role which is Standby compared to other MS series.

This role adds a better management redundancy, since even if the Master goes offline it takes over the Master role and it's still possible to configure the whole stack even when the initial Master went offline. With other MS series models it would not be possible to configure the member switches when the Master is offline.

Is this the correct understanding?

Does the Standby switch still send data in this role, is it a full member switch that just takes over the Master role if the Master goes down?

Thanks!

[alemabrahao]

Correct. When it is on standby, it will work as a layer 2 switch, normally it just won't perform layer 3 functions.