Acronis Storage needs to have direct access to the drives dedicated for STS roles. The most recommended implementation is having internal hard drives set for STS roles. Please refer to the Hardware requirements section of the user guide.
Alternatively, STS role can be set to iSCSI drives or to LUNs of a SAN. NAS can also be used (for example, in a virtual environment, when having datastore on a NAS and storing the nodes’ virtual disks there). Using JBOD is only possible in Acronis Storage Express virtualized setup when it is connected to the virtualization host.