Backup appliances include a software application preloaded onto a storage system that is specifically optimized to make the best use of available memory, processor and I/O resources.
Traditional backup software solutions are less expensive than backup appliances, said Lauren Whitehouse, analyst with Enterprise Strategy Group. However, more time and technical skill is required for setup, because additional components of the “stack” need to be procured: The physical server and operating system it will run on, storage media, and networking components.
By contrast, backup appliance solutions are pre-assembled with these components, offering a simpler installation and configuration experience, she said. That all-in-one-appliance approach removes the need to source individual components of a whole solution such as the operating system, backup application, server hardware, and the storage target system.
“In addition, the appliance vendor has pre-tested the configuration, security hardened it, and optimized it to perform for its backup software application, potentially reducing the user’s administrative overhead for maintaining the system,” said Whitehouse.
This approach reduces the complexity and cost of integrating different components into an ad hoc system. Whitehouse also noted that since the system is sourced from a single vendor, interactions from purchase to support are streamlined.
Greg Schulz, the founder of the analyst firm StorageIO, said some backup appliances support policy-based tiering across back-end direct attached or networked access-based disk and tape storage mediums. Still others are adding support for gateway functionally to access cloud storage services such as Amazon and Rackspace.
“Most appliances also include data footprint reduction (DFR) technologies such as compression, dedupe, policy management and storage tiering,” he said.
According to Schulz, a backup appliance ought to provide a good balance of ease of acquisition, configuration, deployment and ongoing management.
However, depending on the specific implementation, Schulz said, the ‘con’ of purchasing an appliance has to do with whether it will scale with stability in terms of performance, availability, capacity and economics. The scale of the specific solutions also differs in terms of ability to support cloud gateway functionality natively rather than through a third-party standalone appliance.
“Beside price, speeds and feeds, functionality can vary in terms of how it is implemented, such as global or local dedupe, replication, direct path to tape, which cloud services are supported, management tools -- including integration with snapshots -- applications and backup tools,” he said.
Also, according to Schulz, usage and adoption patterns among users vary considerably. Some organizations are using backup appliances to replace local tape libraries that have been redeployed for archiving or for holding “master gold backups.” Some organizations have even used appliances to replace tape altogether, while still others use them as a policy manager to move data between disk-based backups, tape, and deep archive or cloud storage, he said.
While the value of a software-based approach is that you can source the software with the flexibility to configure it onto your servers, with your choice of storage to fit your needs, appliances may limit your options, he said. “Another downside of adopting a backup appliance is that it may force you to buy your storage from a single vendor rather than being able to shop around or use your existing storage capabilities,” he adds. As such, it is important to evaluate the functionality you need now, and what you may need going forward when choosing a backup appliance.
Comparing backup appliance options
Although the market has even more backup appliance offerings, Whitehouse said five vendors have offerings that are worth a look:
The Symantec 5200 Series (5200 and 5220). This is an all-in-one hardware/software/service and support solution. The 5200 is based on NetBackup 7 with native deduplication deployed at the source or proxy in an inline or post-process configuration, she said. It offers 32 TB of usable capacity and 10.5 TB/hour aggregate throughput. Off-site copies are facilitated by device-to-device replication, as well as output to tape media for long-term retention. The 5220 offers six Ethernet ports and two FC ports -- dedicated to tape out -- with the option of two 10 GbE ports and four FC ports for SAN clients, she said.
Unitrends. Unitrends appliances range from small desktop models (Recovery -172, - 212, -312), 1U form factor models (Recovery-612, -712, -713, -813), and a 2U model (Recovery-822), from 1 TB to 13 TB. “The range of operating systems, applications and hypervisors [that Unitrends devices] back up is impressive,” said Whitehouse.
Arkeia. This vendor provides its backup/recovery solution as standalone software, a virtual appliance and a physical appliance. Whitehouse said its 2U rack-mountable physical appliances address companies ranging in size from SOHO to medium-sized enterprises. Arkeia facilitates backup of dozens of operating systems, applications and hypervisors to disk, with the added capability of making copies on tape media or transferring copies to an Amazon or Nirvanix cloud repository, she said.
FalconStor. FalconStor provides its Continuous Data Protector solution in an appliance form factor, in addition to software only and virtual appliance offerings. FalconStor has solutions that range from small business through large enterprises. Its CDP 100 appliance accommodates 1TB of data, the CDP 300 stores up to 8 TB, the CDP 500 stores up to 132 TB and the CDP 700 stores up to 192 TB. FalconStor offers high availability features through redundant components -- power, fans, networking -- as well as a clustered, two-node, configuration with multi-pathing in the CDP 700 solution, said Whitehouse.
EMC. EMC Avamar is available as a software solution, virtual appliance and physical appliance. Its physical appliance has a scale-out architecture where performance and storage can scale linearly with the addition of more nodes, which EMC refers to as its Redundant Array of Independent Nodes (RAIN) architecture. EMC offers five models in its appliance line, ranging from single-node solutions (DS-1, which can store up to 7.8 TB) or its multi-node solution (DS-5 through DS-18 which can store up to 124 TB).
Quantum and Acronis also recently announced similar backup devices.
Schulz advises users to look at the interoperability of backup appliances in relation to their current or existing software, tools, and configurations before investing in any vendor’s products.
“In other words, the appliance should work for you rather than you having to work for the appliance,” he said.