In this fast-paced world, there is one thing most computer users have in common: We have all lost data at one time or another. For the lucky ones, this is not a painful experience — just one of inconvenience.
Unfortunately for others, the data loss is impacting because the lost data was irreplaceable and valuable. The good news today is that there are many types of data storage solutions available.
As you think about how to protect your data, it’s important to understand the different ways in which data can be lost.
Device failure can happen when there is a corrupted area on the disk where your file is located. Your entire drive could fail. When this happens, you have to wipe the disk and reinstall the entire operating system.
In the same vein, equipment failure is more complex. This includes a failure like memory corruption within your computer and requires defective equipment to be replaced and information recovered.
Data corruption occurs when application software fails to correctly store information or accidentally overwrites existing information.
User error is the most common reason for data loss. You may remember the “delete *.*” command. In an old-style DOS (disc operating system)-based interface, it was quite common to delete files using that command and disregard the impact it had on all files in the directory. Today, deleting a file is not a catastrophic event.
Site destruction relates to a geographically localized event, such as fire or flood destruction. Recovery from site destruction is complicated as the equipment and the site must be replaced.
Viruses are something we all experience and we tend to feel less threatened by them. However, in order for the global virus database to be updated, someone must be infected and engineers must have enough data to identify and characterize the virus.
Hundreds to thousands of people can be affected by the virus before a detection method is developed and the virus eliminated. If you’re lucky, the virus will only be one of inconvenience and annoyance; however, it could be a virus of destruction and your data could be permanently lost.
Hackers are another way in which data can be lost. Most of the hacking we hear about involves individuals breaking into a system for private information. What we don’t hear is hackers breaking into a system and sabotaging data. Companies that experience a breach are reluctant to report it, fearing the effect on public image or market valuation.
Only when the breach involves private and confidential information of customers are companies required by law to disclose the breach publicly.
Natural disasters are the worst because of their scope and size. Equipment is lost, facilities are destroyed and personnel is unavailable. Recovering from a natural disaster is not as easy as simply relocating to a new building and installing equipment.
Most companies in areas that are vulnerable to natural disasters have disaster recovery plans in place. Recovery usually involves staging equipment in another city and programming the computers there to be brought online quickly. They also have alternative trained personnel who can arrive during an emergency.
Having identified what can destroy your data, it is time to look at some of the basics of data protection.
Time to protect is the amount of time needed for your device to make a copy of your data and verify that it’s been done properly. Different technologies take different lengths of time to complete this process. The time needed to back up your data is known as the backup window and represents an impact because of application unavailability while data is backed up.
Time to recover your information is extremely important for data protection. Some technologies provide the ability to restore lost information instantly while others may take minutes or hours. If you need to be back online immediately, then you need to choose a technology that provides the fastest recovery time.
The recovery point objective involves knowing what the state will be when data is restored — knowing when the data was backed up so that any subsequent changes can be identified. The recovery point is defined as a known state so any additional changes can be applied to bring the data to the current state when data loss occurred.
The level of protection for each technology must be weighed carefully when making your selection. For instance, if you must recover data immediately, you may choose one technology to do the immediate recovery.
However, because of its limited ability to protect against all types of data loss, a second layer of protection may be needed. This is typically referred to as multilevel data protection.
Multiple point-in-time copies are important to provide more than one version of protected files. There are situations in which data is corrupted and you’re not aware of the corruption for many days. If only one copy of your data is made, then your last copy (and therefore the only copy) will also be corrupted.
By creating multiple point-in-time copies, you can go back to a copy which was not affected.
Data protection technologies are generally placed into two categories: fixed storage solutions and removable storage solutions.
Disk-based storage solutions can be comprised of a single disk drive or multiple disks. Some techniques used by fixed storage solutions are disk-based backups, mirroring, snapshots and replication.
Disk-based solutions are not removable and cannot protect against all forms of disaster unless an expensive remote replication solution is installed. A remote replication solution involves replicating the storage system at a remote site and using communication links to transfer replicated data to the site.
These implementations offer protection against device failures, equipment failures, site destruction and natural disasters, yet remain vulnerable to viral attacks and hackers. The only way to assure protection is by having data on removable media and storing it securely.
Tape-based backup is a classic solution focused on tape drives and libraries. Tape is the most cost effective solution from a cost-per-megabyte perspective, and it is the only traditional solution other than optical that offers removable storage suitable for off-site storage. However, the speed of recovery for tape solutions can be slower than snapshots, clones and mirrors.
It’s not a matter of if, but when you will lose valuable computer data. By developing a data protection strategy today, you will be taking out one of the smartest insurance policies money can buy.
Bob Williamsen is vice president of marketing at ProStor Systems.