This should be possible. If you only have one layer, you just do a full-mesh between them. When you add another layer, just do a full mesh between spine and leaf layer, but not between spine and spine, and not between leaf and leaf
Based on the url given previously, i read paragraph like below it have statement "choose one spine switch to be the standby switch". May i know how to choose spine switch as standby? Is it any hidden knob?
Appreciate any feedback
How to Prevent a Split-Brain State
If the links between the spine switches are down, causing the BGP peering to go down, both spine switches are active and forwarding. The downstream aggregated Ethernet interfaces are active and forwarding. This scenario is known as a split-brain state and can cause multiple problems.
To prevent this issue from occurring, choose one spine switch to be the standby switch. Use an event script on the standby switch that is triggered by a BGP peer down event. When the BGP peering goes down, the script checks if the other spine switch is still up using the out-of-band interface. If the other switch is reachable, the script disables the aggregated Ethernet interfaces on the standby switch. The downstream device then only uses the other spine switch to forward traffic.