Does any of this sound familiar?
It has been one of those days; you booted up your computer as usual this morning and instead of giving a cheery beep your hard drive just started to make ominous whining noises and the screen remained stubbornly blank. It looks like you just lost your system disk. When was the last time you tested your backup system to see if it really worked? If the answer is never, you are about to find out about data backups the hard way. Do you have a good backup plan in place that can restore your systems quickly?
Or how about this? Your nephew the summer intern accidentally deleted the file with last month's receivables data. After you have given him a piece of your mind, you realize that fortunately you have an archive copy of the critical file on a backup CD that you make every month when reconciling the books. Aren't you glad that you instituted that system of regular archiving last year?
Then there is the IT consultant is recommending paying extra to put a RAID array into the company file server. He says something about how you cannot afford to have the server fail, so high availability would be a good idea. Isn't the existing tape backup system good enough?
A well-planned backup strategy with appropriate systems will save you both time and money when your computer systems fail or files are accidentally deleted — accidents will happen. Since hardware prices and connectivity costs have plummeted, backup systems and strategies have changed a lot, too. Redundancy that was formerly only available to large corporations is now within reach of even the tiniest company. Backup is the best insurance policy you can have for your business critical data, but there are some important things to think about when developing an overall backup system plan. Let's discuss the fundamentals of backup strategies and systems that make sense for smaller companies.
Backup Systems Fundamentals
Backups actually serve two functions for an organization and the requirements for each are quite different. When a system experiences catastrophic failure it needs to be completely restored to the state it was in prior to failure — as quickly as possible. RAID and mirrored systems are generally used for this purpose. When simply archiving old data and retrieving files that people might have accidentally deleted, you are more concerned with a long-term record, so it is more important to maintain a series of historical backups. Tape or CD backups are better suited for this purpose.
Ideally, backups should be as automated as possible, so use one of the many cheap backup software utilities available. Even the backup built into Windows XP Pro is adequate for a very small system. Generally a weekly or monthly full backup and daily incremental backup plan is sufficient for most small companies. It is also very important to test the restore mechanism before you actually need it.
The standard method for server backup today is a combination of a server RAID (either software or hardware based) for fast system restoration from a tape backup for file retrieval and archive purposes. With the new tape stackers and the higher density tapes (160GB of compressed data will fit on a single tape), vast amounts of data can easily be backed up quickly. This combination reduces restore times in the event of a system failure and increases the chances of maintaining data integrity, while allowing for simple selective individual file restoration and archival storage.
There is one other consideration in designing or selecting an appropriate backup system for your company. You can either chose to purchase the equipment and set up an in-house backup system or you can take advantage of the many service providers who offer on-line backup systems. The advantage of using a backup service is no capital fixed costs, maximum flexibility and remote access. If your business is mostly conducted remotely, this might be your only viable option. The disadvantage is that if your system fails while off-line, restoration is impossible until it is restored enough to be on-line again.
Some General Recommendations
Face it, backup seems boring, costly and time consuming; but like buying insurance, you risk jeopardizing your entire business if you do not purchase it. Fortunately, there are only a few key basics to understand in implementing an inexpensive system that will satisfy most company's requirements.
- Determine the critical business need — is high availability critical for your business or lower costs?
- Determine the relative importance of disaster recovery, systems failover and file restoration.
- Develop and implement a disaster recovery plan. Even if it is as simple as a single piece of paper with a list of your software key, every little bit helps in recovery.
- Consider a remote backup service — they are monthly expenses not capital equipment and they provide more flexibility. As your backup needs change, changing the service terms are simple.
- Use a tape rotation system and assure that tapes are properly cared and accounted for.
- Make sure there is adequate redundancy (at least one extra copy of all computer data).
- Make sure backup media are stored safely and off-site (Remember if it is in a bank safe deposit box you will not have 24 hour access).
Backup System Recommendations
If your servers do not have RAID implemented, unless there are serious cost issues, then I would highly recommend adding that functionality. The best methodology for systems restoration (particularly in a high availability environment) is completely mirrored systems using either a RAID array for seamless disk failover or for a fully redundant system, a cluster of servers that failover between each other. If RAID is not implemented, the tradeoff is a very slow system when restoring from backup tapes or the backup service.
If the servers already have RAID implemented, then you have the choice of either installing a networked tape stacker unit or using a commercial network backup service. If your company is very small, at the very minimum you should be backing up using your system CD-RM unit and built-in backup software. The choice is dependent on your specific business situation, how you want to allocate costs, the location of the servers, security issues and future expansion plans.
The productivity losses caused by catastrophic system failure and the lack of a good backup system cannot be underestimated. At the very minimum, you need automated tape backup for your critical systems. The decision to use a RAID and high availability is dependent on your tolerance for downtime. If you cannot afford to be out for a day or two, invest in the RAID system and automated failover. You will be glad you did. With the current prices for these systems, you literally cannot afford not to have a good system, so what are you waiting for?
Beth Cohen is president of Luth Computer Specialists, a consulting practice specializing in IT infrastructure for smaller companies. She has been in the trenches supporting company IT infrastructure for over 20 years in a number of different fields including architecture, construction, engineering, software, telecommunications, and research. She is currently consulting, teaching college IT courses, and writing a book about IT for the small enterprise.