Dell PowerFlex 4.6.x Technical Overview

Software

The PowerFlex virtual SAN consists of the following software components:

• Meta data manager (MDM): Configures and monitors PowerFlex. The MDM can be configured in redundant cluster mode, with three members on three servers or five members on five servers, or in single mode on a single server.
  NOTE:It is not recommended to use single mode in production systems, except in temporary situations. The MDMs contain all the metadata that is required for system operation. Single mode has no protection, and exposes the system to a single point of failure.
• Storage data server (SDS): Manages the capacity of a single server and acts as a backend for data access. The SDS is installed on all servers contributing storage devices to PowerFlex. These devices are accessed through the SDS.
• Storage data client (SDC): A lightweight device driver that exposes PowerFlex volumes as block devices to the application that resides on the same server on which the SDC is installed.
• Storage data replication (SDR): A component that acts as a proxy between the SDS and SDC that must be installed for replication.
• NVMe target, also known as storage data target: Manages the translation of I/O from the internal PowerFlex protocol to the NVMe over TCP standard.
• NVMe initiator: NVMe driver that connects to the NVMe over TCP storage system to consume storage, and uses an NVMe multipathing driver for high availability and load balancing.

Depending on the preferred configuration, the software components are installed on the server and create a virtual SAN layer that is exposed to the applications that reside on the servers.