We are using AKS 1.19.1 in our sandbox environment and have both system and user nodepools seperately. We have multiple applications running in our user nodepools along with istio as service mesh. Current node count of the usernodepool is 24 and auto scaling is enabled.

Now as part of cost optimisation, we are planning to scale down the usernodepool to zero during the non working hours ( say after office time or during night time).

Reference:-  https://docs.microsoft.com/en-us/azure/aks/scale-cluster

Will this be recommended way to do scale down to zero nodes for such a cluster with nodepool size of 25 nodes

if yes,

When we renable autoscaling property (everyday after making the count to zero at night) , will this automatically increase node count and application pods will be auto sterted or, we need to rollout the restart of the pods seperately?

What are the factors it depends to back the normal running state and how long it may take?

Is there any way to schedule this feature of scaling down to zero during night and then again renable autoscaling property at morning automatically