In a distributed storage of data objects in a cluster system, a data object is distributed across a group of node apparatuses in units of data blocks. For each child object, the metadata structure of the respective child object is stored to one of the node apparatuses of the group of node apparatuses for managing locations of data blocks of the data object and includes a root metadata node and one or more direct metadata nodes, optionally further including one or more indirect metadata nodes; and the metadata structure of the parent object is distributed across the plural node apparatuses of the group of node apparatuses for managing locations of child objects of the data object and includes, on each node apparatus of the group of node apparatuses, a root metadata node and one or more direct metadata nodes, optionally further including one or more indirect metadata nodes.