What are the recommendations regarding the cluster node id?

Question

Answer

At installation time, Jahia generates a UUID to ensure that each cluster node id is unique.

From https://wiki.apache.org/jackrabbit/Clustering#Unique_Cluster_Node_ID it is safe to use any kind of identifier for this property as long as this ID is unique on each cluster nodes. It could be changed by a script once the Jahia folder has been cloned.