D-Link xStack Storage DSN-4200 16 Bay 3U 8x 1 GbE iSCSI SAN Array

The Storage Area Networks (SANs) have traditionally been reserved for complex Fibre Channel networks. The recent introduction of iSCSI has extended the powerful centralized storage capabilities of SAN technology to IP networks. By utilizing existing Ethernet technology, the costs associated with Fibre Channel switching, separate host bus adapters, expensive storage subsystems and administration is significantly reduced. The iSCSI SANs leverage the Ethernet infrastructure and standards that are already familiar to most IT personnel.

The DSN-4200 iSCSI SAN Array supports Multi-path I/O (MPIO), Multiple Connections per Session (MCS) and Link Aggregation Groups (LAG) for unmatched network flexibility, performance and resiliency. This allows their 1 GbE data ports to be grouped together for full line speeds of up to 850 Mbps bandwidth.

The DSN-4200 iSCSI SAN Array supports 16 internal SAS/SATA hard drives and with the addition of up to four DSN-4000 expansion arrays, can scale to a total of 160 TB of raw storage capacity using 2 TB drives.

The DSN-4200 iSCSI SAN Array combines both networking and storage functions into a single specialized Application Specific Integrated Circuit (ASIC), by utilizing a SoC design. This SoC combines 10 Gbps iSCSI, TCP and IP offload, 12 embedded processors and storage virtualization firmware onto a single chip. The tight integration of these functions eliminates interoperability, timing and support issues found in competitive products that offer a "discrete implementation" wherein various components are selected separately, then assembled.

The iSCSI SAN Array supports RAID level 0, 1, 1+0 and 5 configurations (striped sets, mirrored sets, striped mirrored sets and parity sets) for data protection and performance.

The embedded, user-friendly IP-SAN Device Manager (IDM) provides a comprehensive console for system management. This suite of utilities allows monitoring and control of the SAN array via the Storage Management Initiative-Specification (SMI-S) command set that boasts a rich set of management features. With a secure server, users can remotely configure and monitor their SAN arrays over the Internet.

The DSN-4200 iSCSI SAN Array also provides an advanced set of features for efficient management and optimal storage performance. For the fastest RAID performance offered in the industry, D-Link's adaptive cache management provides write coalescing and multi-stream read-ahead on a volume basis, optimizing cache utilization and performance in an application dependent manner. Volatile cache data protection is afforded via an on-board battery supporting cache memory for a minimum of 72 hours. A write-back or write-through cache memory policy can be selected manually or automatically, depending on the status of the battery's charge.

The DSN-4200 supports jumbo frames and VLAN tagging to segregate traffic into isolated zones for secure access, improving network throughput and reducing CPU overhead. D-Link's volume virtualization technology utilizes the concept of storage extents, which are the fundamental building blocks used to enable features such as RAID, online capacity expansion, volume reconfiguration and migration. Each disk drive can contain multiple and divergent RAID configurations instead of requiring dedication to a single RAID set. This technology allows for the support of mixed disk drive capacities for volume creation. Volume capacity expansion, volume reconfiguration and RAID level migration are performed online with minimal impact to users. Users can quickly deploy a SAN using inexpensive SAS or SATA disk drives and simply add more drives as needed.

An iSCSI SAN Array can prove to be a valuable tool to supplement a network storage foundation. Whether providing a low-cost block-based solution for data backup and recovery, replacement of Direct Attached Storage (DAS) that provides secondary online storage or providing up to 850 Mbps bandwidth for security surveillance and video post-production applications, the DSN-4200 iSCSI SAN Array may provide the performance and functionality needed.