@WhitW-6534 Apologies for the delay in response and all the inconvenience caused because of the issue.
The available node types in the service fabric cluster are derived from the properties of the list of active nodes.
In the cluster manifest, there is a "NodeList" element which is a grand-child of the "Infrastructure" element in the XML format of the manifest. The elements of type "Node" are children of "NodeList" elements and have a property "NodeTypeRef". Please refer to the snippet on the cluster resource definition page here
There should also be a list of "NodeType"s and their properties. The existence of a node type in the list of node types does not guarantee there are any active nodes of that type at any given time depending on how the cluster is operated. There are snippets of what the NodeType list looks like in XML and JSON in this section.
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