hi.
i merged the two threads as i saw the duplication. and noticed you also asked about the ipspace for that interface.
i think you can't change the ipspace of the Vserver object that hosts the MGMT interfaces (the cluster_name SVM) it have to stay in the default one.
i was looking at this years back and prtty sure it was not possible. also don't see it possible here (you can't change any SVM IPSpace post creation) :
https://www.netapp.com/us/media/tr-4182.pdf
i do encourage you also to have a read on this above DOC for the ipspace typical use cases. as it's very rear for someone that is not service provider to need it and can create some pain.....
Gidi