The enterprise SAN comes with a number of fairly common features and capabilities, such as capacities around the petabyte mark or above; the ability to handle all drive types including SSD; large port counts in multiple protocols; and functionality that is now standard in midrange arrays, such as thin provisioning, automated data tiering and replication.
But the enterprise SAN market is not a uniform one. Some enterprise storage area networks are defined by their huge potential capacities or their modular architectures that allow scale-out-type growth and aggregation of processing power and bus bandwidth. Others are defined by their support for the Ficon mainframe protocols or storage virtualisation capability, which can create a large pool of storage from multiple vendors’ arrays. Others, while having SAN block-level access, offer NAS support as a major characteristic. SSD support is common to all, but not always in the form of standard drive types.
Here we survey the key enterprise SAN vendors and products in turn.
According to EMC, which announced a major upgrade in May 2012, Symmetrix VMAX now offers up to three times the performance and more than twice the usable capacity of other enterprise SAN offerings. The top-end 4 petabyte (PB) capacity VMAX 40K can accommodate as many as 3,200 2.5-inch or 2,000 3.5-inch (Fibre Channel, SAS, SATA and SSD) drives and is aimed at customers building cloud infrastructures and high-performance OLTP/OLAP applications. The three-strong product family starts with the VMAX 10K (formerly VMAXe), with a maximum 1.5 PB capacity and 1,080 drives, with 64 ports providing Fibre Channel, Gigabit Ethernet (GbE), 10 GbE, 10 Gbps Fibre Channel over Ethernet (FCoE) and iSCSI connectivity. The 2,400-drive, 2 PB VMAX 20K and the VMAX 40K both offer 128 ports and FICON connectivity for mainframes.
EMC's DMX platform uses the Direct Matrix architecture, which is older than VMAX’s Virtual Matrix architecture. It consists of as many as eight director modules and offers up to 64 4 Gbps Fibre Channel and ESCON ports; 32 FICON ports; 48 1 Gbps iSCSI ports for each director module; and support for as many as 2,400 SATA, SAS and SSD drives, totalling a maximum capacity of 1.9 PB.
Eternus DX8700 S2
The Eternus DX8700 S2 provides nondisruptive capacity upgrades using modules and can house up to 3,072 disk drives for a total capacity of 4,608 TB. It will connect over Fibre Channel, FCoE and iSCSI with up to 128 ports, and it offers tiering using a combination of SAS, near-line SAS and SSDs. It offers data protection via self-encrypting drives, redundant components and interconnects, and local and remote replication. The device does not support mainframe protocols.
Aimed at providing high availability for mission-critical data, the XP P9500 Storage system supports clustering and remote mirroring to provide multisite disaster recovery. It also features thin provisioning, offering up to 2 PB of raw capacity from 2,044 SAS drives, connected by 160 8 Gbps Fibre Channel, 160 8 Gbps FICON or 80 10 Gbps FCoE ports. HP licenses the XP technology from Hitachi, and it is the same basic platform as the Hitachi Data Systems (HDS) Virtual Storage Platform (VSP).
HP 3PAR P10000 Storage Systems
Before 3PAR was acquired by HP, its products were designed on a modular architecture with thin provisioning. HP retained the 3PAR branding to help with enterprise SAN market positioning. The P10000 consists of a chassis with nine modules, starting with a V400 base node, plus V400 and V800 upgrade nodes, and two V800 controller nodes. The V800 scales to 1,920 drives and 1.6 PB of raw capacity. Both the V400 and V800 support SSDs, Fibre Channel and SATA drives. All provide 10Gbps iSCSI and 8Gbps Fibre Channel ports, with the V400 supporting up to 96 ports and the V800 up to 192 ports. Unlike the XP P9500, 3PAR storage lacks FICON mainframe connectivity.
3PAR T-Class Storage Systems
The two-strong T-Class consists of the T400 and T800, with capacities of 400 TB and 800 TB, respectively. Connectivity is via 4 Gbps Fibre Channel with a maximum of 64 ports for the T400 and 128 ports for the T800 or 1 Gbps iSCSI (16 and 32 ports). The T400 supports from 16 to 640 drives, and the T800 supports 1,280 drives. All drives types are supported, including near-line enterprise drives.
Hitachi Data Systems
Universal Storage Platform
Hitachi's USP offers storage virtualisation capabilities across external arrays from heterogeneous vendors as well as its own internal capacity. It scales up to 247 PB of capacity under its management, including as much as 507.5 TB of Fibre Channel or 1,134.5 TB of internal SATA storage. The family consists of the USP V and the USP VM, housing up to 240 SATA and Fibre Channel drives, including spares, and up to 128 SSDs. Protocol support includes as many as 112 ESCON and 224 FICON, 8 Gbps Fibre Channel or FCoE ports. The USP is the older of Hitachi’s enterprise SAN arrays.
Virtual Storage Platform
Hitachi's VSP emphasises high availability and, like the USP, enables the consolidation of multivendor storage in a single pool. It can be scaled out, and by virtualising external storage systems adds its functions, such as tiering, to those external arrays. The VSP supports up to 256 2.5-inch and 3.5-inch SAS, SATA and SSDs for a maximum internal capacity of 2,521.1 TB, although it can control up to 255 PB when attached to external storage. It supports up to 192 Fibre Channel or FICON ports or 96 FCoE ports. The VSP began shipping in late 2010 and will replace the USP.
System Storage DS8000
IBM's System Storage DS8000 family offers automated tiering, performance management and asynchronous replication. As you might expect given IBM’s mainframe roots, the DS8000 range includes Ficon connectivity. Capacity ranges between 5 TB and 2 PB on the two devices. The DS8800 is newer than the DS8700, having been launched in November 2010. It has the faster Power 6+ processor, 8 Gbps Fibre Channel connectivity (the DS8700 has 4 Gbps) and supports SAS drives where the DS8700 supports only 3.5-inch Fibre Channel. The DS8800 also offers self-encrypting drives.
XIV Storage System
The XIV is a self-tuning, high-density, parallelised system with a 6 TB SSD option for added performance. It is aimed at virtual environments and cloud services that need high levels of availability. It consists of two models, the entry-level XIV and the XIV Gen3, both housing between 72 and 180 drives. The XIV supports SATA drives, while the Gen3 uses SAS drives, and SSDs for caching. Both offer 24 Fibre Channel ports -- 4 Gbps for the XIV, 8 Gbps for the Gen3) -- and six and 22 iSCSI ports, respectively. Unlike IBM’s DS8000, XIV storage does not support mainframes.
The FAS6000 family provides SAN capability alongside the NAS filer capability for which the vendor is best known. The top-end model, the FAS 6080, supports up to 1,176 SAS, SATA and Fibre Channel drives for a maximum capacity of 2,352 TB; the entry-level FAS6040 offers 840 drives delivering 1,680 TB of maximum capacity. Both models include 12 1 GbE and 16 4 Gbps Fibre Channel ports, expandable using adapter cards. While the FAS6000 family does not support SSDs in the array, it does allow for installation of NetApp Flash Cache cards to accelerate performance. NetApp does not support mainframes.
Manek Dubash is a technology and business journalist with more than 25 years of experience.