The storage node is a storage server that is connected to the storage devices, consisting of hard disks( HDD) or solid-state drives (SDD), and the backup server and controls the creation of backup copies and hierarchical storage management.
A storage node can also be a virtual machine or a virtual logical unit number( LUN), which is used to access the storage devices. Virtual technology is related to the increasing use of virtual storage area networks( VSAN).
Storage nodes are equipped with special backup software that controls data stored on other storage media. Multiple storage nodes are often bundled and managed in a single storage pool. This has the advantage that if one component fails, availability remains.