HI @Alex13529 - by setting up a Warm spare you're taking care of L3 redundancy.  I don't believe you'll be able to setup link aggregation using both the Active and Warm spare switches as they won't and can't be part of the same stack.   https://documentation.meraki.com/Architectures_and_Best_Practices/Cisco_Meraki_Best_Practice_Design/Best_Practice_Design_-_MS_Switching/General_MS_Best_Practices   https://documentation.meraki.com/MS/Layer_3_Switching/MS_Warm_Spare_(VRRP)_Overview ... View more