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To understand how Storage Data Server (SDS) system maintenance is performed, we must first consider the basic architecture of PowerFlex itself.
Servers contributing media to a storage cluster run the Storage Data Server (SDS) software element. The SDSs enable PowerFlex to aggregate the internal media while sharing these resources as one or more unified storage pools out of which logical volumes are created.
Servers consuming storage volumes leverage the Storage Data Client (SDC) which provides access to the logical volumes using the host’s SCSI layer.
Note: iSCSI is not used but is instead, a proprietary, resilient load-managing, load-balancing storage protocol that runs over TCP/IP storage networks.
The Meta Data Manager (MDM) controls the flow of data through the system but is not in the data path. It maintains volume mapping across the SDS cluster, distributes it to the SDCs, informing them where to place and retrieve data for each part of the volume address space.
These three base elements are the foundation of this unparalleled software-defined storage solution, one that scales linearly to hundreds of SDS nodes.