@41583054 Apologies for the delay in response.
One of recommended method to ensure pods are scheduled on separate node pool is by using labels. Information about can be read from here.
In order to reduce cost, what can be done is to keep the node pool size to 0 and pod won't be scheduled and will be in pending state. Whenever this service needs to be provisioned (the pool size can be increased to required size) and the pod would be scheduled on that node.
Apart from this, I can't think of any way to achieve the same.
Hope that help.
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