Chapter 2. System overview 19
Any additional licenses must be procured per every enclosure where they are planned to be 
used. For example, if you plan to build a disk array with compression enabled in one 
enclosure only (no matter if this enclosure is the control or expansion enclosure), you must 
purchase only one compression license.
2.4  IBM Storwize V7000 hardware
Along with the previous release of the IBM Spectrum Virtualize V7.3, IBM introduced a 
hardware refresh for the IBM Storwize V7000 platform (code name Gen2) with another 
update in V7.8 (Gen2+). These improvements are further enhanced with the most recent 
version of IBM Spectrum Virtualize software V8.2. 
This section introduces and partially repeats these hardware changes and software 
improvements that are associated with these updates. They include the following changes 
and improvements:
/SM590000New internal component layout, such as canister and ports
/SM590000Integrated battery pack within node canisters
/SM590000Enhanced scalability and flexibility with 16 Gbps I/O adapters
/SM590000Improved Real-time Compression engine with hardware assistance
/SM590000Extended disk drive support
/SM590000Cache upgrade option to 128 GB per canister
To meet these objectives, the base hardware configuration of the IBM Storwize V7000 Gen2 
and Gen2+ were substantially improved to support more advanced processors, more 
memory, and faster data interfaces.
2.5  IBM Storwize V7000 components
The IBM Storwize V7000 is a modular, midrange virtualization RAID storage subsystem that 
uses the IBM Spectrum Virtualize software engine. It has the following benefits:
/SM590000Brings enterprise technology to midrange storage
/SM590000Specialty administrators are not required
/SM590000Client setup and service are simplified
/SM590000The system can grow incrementally as storage capacity and performance needs change
/SM590000Multiple storage tiers are in a single system with nondisruptive migration between them
/SM590000Simple integration can be done into the server environment
The IBM Storwize V7000 consists of a set of drive enclosures. Control enclosures contain 
disk drives and two nodes (an I/O group), which are attached to the SAN fabric or 10-gigabit 
Ethernet (GbE) fast Ethernet. Expansion enclosures contain drives and are attached to 
control enclosures.
The simplest use of the IBM Storwize V7000 is as a traditional RAID subsystem. The internal 
drives are configured into RAID arrays, and virtual disks are created from those arrays. With 
IBM Spectrum Virtualize software, this usage is extended by the deployment of distributed 
RAID arrays, which shrink the reconstruction time of failed drives.
IBM Storwize V7000 supports spinning disks and flash drives. When different tiers are used, 
the IBM Storwize V7000 uses IBM Easy Tier to automatically place volume hot spots on 
better-performing storage. Even without the Easy Tier enabled, the Storage Pool balancing is 
available and enabled by default to equally distribute workload equally across all MDisks in 
that tier.