my name is Chriz Ott, I'm working for the Transition Team at NetApp.
Thanks for that question, I have just had asked that to product management recently.
The limit for the number of IPSpaces in a cluster is depending on the number of nodes that you have installed, as this limits the number of SVMs you can create.
4 node cluster 512 data SVMs per cluster -> 512 custom IPspaces max per cluster 8 node cluster, or larger 1024 data SVMS per cluster -> 1024 custom IPspaces max per cluster
Keep in mind, that an IPSpace is not necessarily required in order to achive Secure Multi Tenancy (SMT). Even without an IPspace no data can traverse from one SVM to another, seperating different customers on different SVMs securily. The major benefit of IPSpaces is the ability to assign one and the same IP address multiple times within the same cluster.
Hope this helps.
P.S. if you feel this post is useful, please KUDO or “accept as a solution" so other people may find it faster.