The SoftLayer_Network_Storage_Credential data type will give you an overview of the usernames that are currently attached to your storage device.
This is the id of the type of credential that this object represents.
Type: integer
These are the SoftLayer_Network_Storage_Allowed_Host entries that this credential is assigned to.
Type: SoftLayer_Network_Storage_Allowed_Host
These are the types of storage that the credential can be assigned to.
Type: SoftLayer_Network_Storage_Credential_Type
These are the SoftLayer_Network_Storage volumes that this credential is assigned to.
Type: SoftLayer_Network_Storage[]
A count of these are the SoftLayer_Network_Storage volumes that this credential is assigned to.
Type: unsigned long