I had issues with my master data storage domain and the only way was to set the hosts in maintenence mode ,delete the datacenter so i can recreate it....
I managed to delete the datacenter and the storage domains , and created a new datacenter , but now the existing clusters are not part of a datacenter and trying to add them to the datacenter gives out this error below
Error while executing action: Cannot edit Cluster. Changing management network in a non-empty cluster is not allowed.
and by non empty i guess it means there is a host inside that cluster ? fair enough