The NDMP three-way backup, also known as the remote NDMP backup, is shown in the following figure.
In this backup mode, the tape devices are connected to the backup media server. OneFS does not detect tape devices on the PowerScale cluster and Fibre Channel ports are not required on the PowerScale cluster. The NDMP service runs on the NDMP server or the PowerScale cluster. The NDMP tape service runs on the backup media server. A DMA on the backup server instructs the PowerScale cluster to start backing up data from the PowerScale cluster to the backup media server over the network. The backup media server moves the backup data to tape devices. Both the servers are connected to each other across the network boundary. Sometimes, the backup server and backup media server reside on the same physical machine.