Data Backup Methods
Aug 1, 2002 12:00 PM, By Kevin McNamara, CNE
Did you know that 93 percent of companies that lost their data center for 10 days or more due to a disaster filed for bankruptcy within one year of that disaster? While the term data center in this case may apply to a different type of business, radio facilities rely heavily on network servers to support their on-air programming and business functions. Here are more interesting statistics:
- A hard drive crashes every 15 seconds
- 2,000 laptop computers are stolen daily
- 32 percent of data loss is caused by human error
- One out of five computers suffer a fatal hard drive crash
Critical data loss can occur on a server, workstation or laptop, so it is important to understand what methods are currently available to back up data and how to properly implement data backup procedures.
Is it necessary to back up all of the data on a PC? The answer might change for every user, depending on his needs. Data residing on a PC, whether it is a server, desktop or laptop, using any operating system, can be divided into two primary categories: program or data files.
Program files are those that permit a program to be executed properly on the PC. Data files are those that support the application or contain raw data.
Figure 1. A breakdown of typical sources of data loss within a business.
In many cases, backing up data files may only be sufficient to recover from a major drive crash, assuming the user has ready access to the original program disks. If operating system files become damaged, it may be necessary to re-install the application. However, several software vendors offer programs that create an image of the installed operating system, including its configuration files that can be copied to a disk. These typically store data on a CD-ROM. These programs also load a set of start-up files that permit the PC to boot directly from the created backup disk.
Loss of data can be caused by a number of factors such as hard drive failure, mechanical or electrical; viruses that may replace or corrupt data files; human error, inadvertent formatting of a drive or erasure of certain data; or theft of PC containing critical data. Figure 1 shows a breakdown of some of the typical sources.
The decision as to which type of backup system may be appropriate is based on a number of issues, such as the potential loss of revenue or operational flexibility should date be lost; the cost of purchasing, installing and maintaining a suitable backup solution; the time required to backup data; the ease of backing up data, i.e. manual vs. automated back up systems; the life span of the backup media; and personal preference.
A final factor in determining a proper data backup solution is whether the backups will be stored on-site, offsite or over the Internet.
On-site storage may include something as simple as keeping copies of the backup in a fireproof safe or duplicating information on drives located in other rooms or floors.
Offsite backups provide the highest level of protection for data because the backups are located in a different premise, such as in the next building, or a different city, state or country. Many large companies, such as financial institutions and telecommunications companies, mirror data across several data centers throughout the world. Using this approach, even a major disaster - an earthquake or flood - would not cause systems to fail and incur a loss of data.
A summary of the most popular forms of data backup used.
Internet storage sites are becoming popular methods for storing backup data. The benefits are similar to that of traditional offsite storage, but without the need to purchase and maintain equipment at the remote locations. Another advantage is that the data is available through any sufficient Internet connection, which helps to return a system to service from alternate locations. An example would be an office fire. Internet-based storage is typically priced by the amount of data stored that makes it a viable option for large organizations or individual users. The downside of Internet-based storage is the inability to ultimately retrieve that backup data without an Internet connection.
Servers play a critical role within any organization that uses a network to store and share data between two or more users. While the broad definition of a network requires at least two users, most are much larger and have built a dependency on the data that resides within their servers. Total loss of data can mean severe operational and financial impact for the affected company.
Storage area networks (SAN) provide the ability to mirror data amongst backup servers spread over a local or larger geographic region. Disk mirroring can also be accomplished using a redundant array of independent disks (RAID), where data can be simultaneously written to multiple disks using a variety of techniques. Other methods include optical and magnetic based storage devices such as tape, CD-ROM and magneto-optical drives.
Network-connected workstations can be backed up to remote network drives. In many cases the network is configured such that all data is automatically saved to a network drive by default. The user of the workstation can download copies of data to the local machine, but the original remains on a server. A good example of this is Microsoft Exchange Server. Users connect to the Exchange server using Microsoft Outlook, but all of the e-mail, contact information and calendar information resides on the remote server. To retrieve the latest information on the local machine, a user synchronizes with the server, which creates copies of the desired folders.
Backing up a PC workstation, either attached or not attached to a network, can also be accomplished locally using more inexpensive hardware solutions such as removable hard drives, CD-RW, high-density magnetic disk drives such as the Iomega Zip or just simple floppy disks.
The options for backing up data from a laptop PC are the same as that of a desktop machine, but laptops are by definition portable, which makes them susceptible to theft and damage. The number of laptop thefts increased 53 percent in 2001 from 2000. I recommend that all laptop PCs use a Windows NT-based operating systems such as Windows 2000 Professional along with formatting the hard drive to the NT File System (NTFS). Using this approach, along with good user name and password schemes, will afford a high level of security. Files saved to drives formatted as NTFS are not easily readable by anyone but the most sophisticated hackers.
McNamara is president of Applied Wireless, New Market, MD.
The Networks articles have been approved by the SBE Certification Committee as suitable study material that may assist preparation for the SBE Certified Broadcast Networking Technologist exam. Contact the SBE at (317) 846-9000 or go towww.sbe.orgfor more information on SBE Certification.