single user mode should have nothing to do with it.
you need to restore the data from *each data node* that participated in the BACKUP.
This is because each node backs up the table fragments that it is the primary replica of.
For a table stored in a 2 node 2 replica cluster, there are 2 fragments per table. F1 is stored in both nodes and Node 1 is the primary replica of this fragment. F2 in both nodes, Node 2 is primary replica of this fragment.
This is so that some operations (notably locking and backup) are load balanced across the cluster.
Restoring only 1 node would restore only 1 fragment, so about 1/2 the data.
Stewart Smith, Software Engineer - MySQL Cluster
MySQL AB, www.mysql.com
Jumpstart your cluster:
http://www.mysql.com/consulting/packaged/cluster.html