The DXi7500, Quantum’s flagship disk-based backup and data deduplication solution, offers a robust feature set and high-quality construction and architecture for the enterprise disk backup market.
With solid throughput and deduplication performance, the DXi7500 can serve as the centerpiece of an enterprise’s VTL (virtual tape library)- or NAS (network-attached storage)-based disk backup infrastructure. What’s more, the product’s management platform, Quantum Vision and StorageCare Guardian, allows administration of many DXi-Series boxes, including support for replicating deduped backups across WAN links-a valuable service in any disaster recovery and business continuity plan.
Designed expressly for backup and archive operations, the DXi7500 offers both VTL and NAS presentations. In addition, the direct tape creation capability writes physical media over dedicated Fibre Channel links and is compatible with backup applications’ direct tape creation protocols.
Support for backup software is excellent-it’s hard to think of a backup console, OS, application and agent combination that isn’t supported. Likewise, support for a variety of tape drive and tape media emulation types is comprehensive.
For instance, organizations that have implemented complex backup and retention policies through backup software such as Symantec NetBackUp can easily remap these jobs onto the newly created VTL on the Dxi7500. This can also be done through complete support of Symantec’s OpenStorage API, which can be especially helpful when backing up multiple locations.
The heart of the DXi7500, and of all Quantum’s products, is the proprietary file system, StorNext. StorNext is a shared disk file system that can be installed on disk arrays in a SAN and is compatible with many client and server operating systems. StorNext is typically used in high-performance storage environments where large files must be shared by many users.
In addition, the DXi7500’s flexibility regarding deduplication is a key differentiator. The product can function as a VTL (up to 64 libraries with 160 virtual drives) and/or a CIFS (Common Internet File System) or NFS (Network File System) NAS. Deduplication is based on per-volume policies and can take place inline (which optimizes for capacity), post-processed (which optimizes for performance), both or neither.
The available combinations of inline and post processing deduplication methods can allow administrators to optimize storage environments to meet the needs of their applications, data and backup/retention policies.
The system, which is designed for use in an enterprise data center, ships as a single full-size four-post rack in its base configuration of 24TB (raw capacity) and scales up in 12TB chunks to a whopping 240TB in two full racks.
Typically, each unit arrives preconfigured with a head or node that is basically a fault-tolerant server running the DXi software and equipped with dual array modules, a 4G-bps Fibre Channel switch and a 1G-bps Ethernet switch. Each component includes hot-swappable redundant power supplies and fans.
Each single array module houses dual hot-swappable Fibre Channel system controllers (active/active) and dual RAID controllers (active/active) with battery-backed-up cache connected to 16 hot-swappable 750GB SATA (soon to be upgraded to 1TB) drives.
Drives are typically configured with a global hot spare-for RAID 5 there are three groups of 4+1 drives and for RAID 6 there is a group of 6+2 and a group of 5+2 drives. Each system can house up to four array modules, and each array module in turn connects up to four expansion modules.
I conducted all testing for this review during a two-day visit to Quantum’s test lab in Englewood, Colo. We spent most of this time elbows-deep in the product’s browser-based management GUI, which is well-organized by function and put context-sensitive help at my fingertips.
It was easy to set up VTLs and NAS shares, as well to assign deduplication, replication and backup policies. I could access systemwide utilities, such as those for space management and replication, through this GUI, along with a range of diagnostic and analysis tools.
I found that Quantum’s management software, which comprises Quantum’s VisionDXi, Quantum Vision and StorageCare Guardian applications, offered a solid set of alerting and reporting options. The interface layout and navigation controls of VisionDXi in particular simplified troubleshooting and made it easy for me to pinpoint potential bottlenecks at the network, SAN and storage system levels.
From the management interface, I could see the status of various hardware components, and set up e-mail or SNMP alerts. I would, however, like to see more granularity in the product’s support for e-mail alerts. For instance, I could set the product’s alert level to “high,” “medium” or “all” to receive predetermined sets of alerts, but I could not set alerts for individual failures or warnings. I’d like to see the option to send network-related alerts specifically to network administrators and disk-related alerts to storage administrators.
My primary goal was to evaluate the suitability of the Quantum DXi7500 as a backup and archive solution facilitating multisite business continuity. Based on the performance reports generated by the system we used in Quantum’s Englewood lab, using real customer data, I saw that the DXi7500 ingested data at 2.2TB per hour to 3.4TB per hour, with dedupe rates ranging from 10 to 30 times depending on the file type and the number of times the same content was backed up.
The system I tested was priced at $385,500, which included the base 18TB system, three 18TB expansion units, a 5TB deduplication software license and one direct path 2 tape license.
To give our lab-tested performance results a real-world grounding, I interviewed a Quantum customer, Howard Marsh, Ph.D., CIO/IT division director of Anchorage Water Waste-water Utility. AWWU is a 285-person utility company that provides clean water and processes waste water for the city of Anchorage, Alaska.
According to Dr. Marsh, AWWU uses Symantec NetBackUp to back up about 6.5TB a day from a varied server environment (Exchange, Oracle, file shares, images and video) each day onto VTL. In this manner it is achieving an 18 to 22 times reduction in data size on one DXi7500 located in its data center while also replicating over a 200M-bps WAN link to a lukewarm DR site located about six miles away.
Dr. March feels that the DXi7500s were an excellent investment and the switch from physical tape to VTL decreases the incidence of errors and drops restore times from 15 to 20 minutes to about 3 minutes.
eWEEK Labs Contributing Analyst Matthew D. Sarrel is executive director of Sarrel Group, an IT test lab and editorial services and consulting firm in New York.