Centralized file-cached storage protects against disaster: consolidated data is easier to protect, easier to manage, and much less expensive. But there's a problem - Disaster Recovery

Computer Technology Review, Sept, 2003 by John Henze

Here's a recipe for disaster: Take large and growing volumes of critical, file-based data, stir in widely distributed networks and users, then add remote offices with poor or nonexistent backup plans and minimal IT resources. The result: Valuable enterprise data is at serious, and continual, risk.

Most businesses would love to consolidate their data into protected data centers--consolidated data is easier to protect, easier to manage, and much less expensive. The problem is that remote users can't access their files over low bandwidth, high-latency wide area networks (WANs). So data and storage remain distributed throughout the enterprise, and protection of that data remains a formidable challenge.

The most commonly employed alternatives (centralized backup, thin clients, data replication, and client-based backups) work to a point, but each has significant drawbacks. New approaches built on file-caching technology are showing great promise in consolidating and protecting remote office data while responding to the user's need for remote file access.

Challenges

Most enterprises are well aware of the value of their companys' data. Government regulations, the threat of data loss, and unmanageable data all add to the pressure of protecting this critical asset.

Government regulations: Regulatory requirements are quickly becoming 800-pound gorillas in the corporate world. For example, the Sarbanes-Oxley Act of 2002 includes general business oversight practices around data retention and corporate records. The government is serious about this: just this past July, government regulators invoked Sarbanes-Oxley in a large civil suit against executives at HealthSouth Corp.

Threat of data loss: The terrorist attacks on the Oklahoma City federal building and New York's Twin Towers demonstrated the potential for data loss on a large scale, and natural disasters put many regional offices at risk. Less dramatic attacks from hackers and viruses can be just as costly as physical disasters, and loss from employee actions (mistaken or malicious) is common and widespread.

Unmanageable data: Managing storage challenges even the most sophisticated enterprises. Storage area networks (SANs) enable storage administrators to consolidate block-level data into centrally managed storage arrays. However, 80% of enterprise data (Word, Excel, and PowerPoint documents; e-mail attachments; graphics applications) is file-based, using file system protocols that resist management and do not operate well over WANs.

In response to these challenges, corporations have carefully protected the data they directly control. They've built and consolidated highly managed data centers with sophisticated data protection and disaster recovery solutions, placing them at corporate and large regional headquarters. These centralized data protection solutions include replication, mirroring, snapshots, tiered storage and online backup.

Although central protection is critical, as much as 60% of a corporation's data resides outside its managed servers on remote networks, desktops, and mobile systems. Not only does a corporation's core data protection scheme core rarely extend to the distant remote offices at the network's edge, but even if it did, it couldn't handle the large volumes of unstructured files. As much as 75% of this "edge data" is unprotected, because it is either ineffectively backed tip or not backed up at all. This is a risky business practice, as edge data can be as critical to the company's survival as its more manageable centralized data.

Some enterprises throw up their collective hands in frustration and do little to protect edge data. Other organizations create corporate backup policies and issue them to all their branch offices, holding each office responsible for its own local backup procedures. The larger offices with IT support personnel may implement workable data protection solutions, but smaller offices without IT staff may make spotty backups or none at all. Businesses that do take action to protect edge data generally either deploy branch office backup solutions, replicate data to their data centers, or deploy terminal servers to eliminate data stored at the edge. However, all of the solutions available for protecting edge data have significant drawbacks.

Branch office solutions including backup servers, backup software, tape drives, and tape media are expensive and not always reliable, and add to the management complexity of a distributed IT infrastructure. The more common replication technologies are temperamental and complex, demand never-ending capacity and bandwidth, and frequently fail over high-latency WANs. Overworked data center staff must also monitor daily replications and backups from dozens of remote offices to make sure they actually complete the backups. And terminal servers, which use the WAN to process and display requests between remote thin clients and centralized application servers, suffer from poor performance and lack scalability.