DAE stands for Disk Array Enclosure.  This is the component of your EMC rack that contains the actual disk drives of the platform, where the data is stored. They come in a multitude of different shapes and sizes, depending on your needs – you can also purchase expansions for a number of existing EMC products.


The Disk Processor Enclosure contains the actual working parts of the EMC device – all the stuff related to block-level protocols. It’s also where the Vault Drives of your device can be found. Generally, you’re not going to spend much time fiddling with this, lest you mess up your system.


Storage Processor Enclosures generally only appear on larger EMC systems. They appear in place of the Disk Processor Enclosure, fulfilling the same general purpose – they contain the storage processors. Again, don’t mess with them.


Storage Processors handle the majority of the operations for an EMC system, including data writing/retrieval, RAID operations, and Read/Write caching. Ultraflex Modules (see below) are used to add additional functionality.

Ultraflex I/O Modules

Justin Paul identifies these as “basically PCIe cards that have been modified for use in a VNX system.” These are fitted into metal enclosures and attached to either storage processors or data movers.

Data Movers and Blades

Data Movers (also known as X-Blades) provide file access to clients through the storage processors of a VNX system. If it helps, Paul recommends thinking of these as Linux systems containing SCSI drives.

Note: Data movers/Blade Enclosures are not present on the VNXe3200, as it doesn’t require separate hardware for this function.


The Control Station manages either the File or Unified components in a VNX array. It’s important to note here that Block-only arrays (such as the VNXe3200) don’t utilize Control Stations.


NAS stands for Network-Attached Storage, and is used to refer to a shared storage device which provides both file system and storage service to servers – all accessed over a shared IP network.

Anyway, hopefully these definitions clear at least a few things up for all of you. If you’re looking to learn a little bit more about any of the stuff we’ve defined here – or you want to know about other terms that aren’t included in our glossary – EMC has a pretty decent dictionary for you to look through.