System Backup Procedures
Most companies today rely heavily on their computer systems, but often their methods to backup this data are flawed or non-existent, especially in small and medium sized businesses. Losing even a week’s worth of data could be extremely costly, time consuming, and possibly difficult or impossible to recover from. This paper outlines some methods you can use to protect your important data and ensure that even a simple hard drive failure can be recovered from quickly.
Backup frequency
The first thing that a company needs to decide is how frequently to perform data backups. Smaller companies may only require daily or, in rare cases, weekly backups. Larger companies may want to look at system backups twice a day.
In order to determine how often a backup should be performed, a company needs to determine at which point loss of data would move beyond being a nuisance to a severe problem. Would losing a day’s worth of order entry, production, shipping, billing, text documents, e-mail, etc. be devastating to your business?
Backup method
Many businesses that perform scheduled backups perform their backup, and then the next time they perform the backup it goes to exactly the same media and overwrites the previous backup. If you follow this routine it is better than having no backup at all, but there are two reasons why this process is incorrect.
- Backups do not always process correctly. You may perform a backup one day, need to recover the files from it, and find that the process failed for one or more files. In this case, you may have a backup but still did not manage to salvage your lost data.
- Problems are not always missed immediately. You may not notice that an important document is damaged or missing from your system for several days, or maybe even longer. Once the backup is overwritten, the new backup will have the same problem as the original file does.
A proper backup procedure preserves your backups for as long as you feel necessary. This is known as a cyclical or rolling backup. An example of this type of backup could consist of the following features.
- Label backup media (CD, DVD, tape, disk) with days of the week. You should have one backup media labeled for each day of the week, including Saturday and Sunday if your business operates seven days a week and you need to backup data on the weekend as well.
- Label weekly backup media. Choose one day of the week that will not be overwritten during the month and create backup media for it for every week of the month instead of the corresponding daily media. For example, if you decide that Friday’s backups will not be overwritten during the month, then create media for Friday Week 1, Friday Week 2, Friday Week 3, and Friday Week 4. Even though some months may have five Fridays, one of the Fridays would be a monthly backup.
- Label monthly backup media. Label backup media with each month of the year. Choose one day each month and perform a monthly backup that does not get overwritten during the year instead of performing the regular daily (or weekly) backup. For example, on the last Friday of each month you might perform your monthly backup.
- Using the above process, you would end up with 20 sets of media and always have at least four weeks of data to select from if you need to perform a recovery.
- Daily media: Monday, Tuesday, Wednesday, Thursday
- Weekly media: Friday Week 1, Friday Week 2, Friday Week 3, Friday Week 4
- Monthly media: January, February, March, April, May, June, July, August, September, October, November, and December
Your own situation may dictate that you alter these procedures. For example, you may find that you need to keep all the weekly backups as well as the monthly backups. This would require 56 sets of labeled media (4 daily media, 40 weekly media, and 12 monthly media – 58 sets of media are required if you perform Saturday and Sunday backups). Or you may not want to overwrite any of your backups during the year, in which case you would need 365 sets of labeled media (366 in a leap year) if you have Saturday and Sunday backups.
Backup storage
Backups should never be stored at any location where the backup was performed. For example, if there were a fire at your company and you had stored your backups locally, it is likely that both the original data and the backup media would be lost.
If your company has more than one office and each one performs their own backups to different media, they could possibly do an exchange and store each other’s media. The best option for many companies is to locate a company that provides off-site backup storage and use them for this purpose. Another option is to perform online backups using an internet based company.
No matter where you store your backups, make sure that the location is secure and that a third party could not easily access your backup data, even if it were to fall into the wrong hands. Password protection for your backups, if that is an option in your backup software, and/or encryption of the data will help safeguard your company’s valuable information.
Backup media
There are several options for backup media. The one you choose will depend on factors such as your company’s budget, the company’s system landscape, and the storage options available to your company. Some of the options are listed below.
- Write once CDs
- Rewriteable CDs
- Write once DVDs
- Rewriteable DVDs
- Tapes
- External hard drive
- USB Flash drive
- Online backup
Some of the factors a company should consider when choosing backup media are listed below.
- Durability. If you want to keep the media for long periods of time, you will need to choose an option that is less likely to suffer damage under normal circumstances.
- Speed. The faster the media accepts data, the faster your backups will be. Tapes tend to be very slow, while CDs and DVDs are much faster.
- Cost. As with anything else in business, cost is always a consideration. CDs and DVDs tend to be the cheapest alternative, while tapes are the most expensive.
- Capacity. You do not want to sit down during your backup and switch media every time it gets full. Unless you have very little information that requires a backup, you would not want to use CDs. An external hard drive will hold the most information without requiring a switch of media during the backup process.
- Reliability. You want to make sure that your backup executes correctly and that the files being written do not introduce errors during the backup. CDs and DVDs tend to experience higher than average errors when recording information. Tapes tend to be the most reliable.
- Portability. If you have systems that are not on the network, you will want a backup solution that allows you to easily access multiple computers, such as CD or DVD backup. If you have a centralized network that can access all files to be stored, you can use a system such as tapes.
The following table compares the various factors for different backup media.
| Durability | Speed | Cost | Capacity | Reliability | Portability | Comments | |
| CD | 3 | 3 | 3 | 1 | 1 | 3 | Not advisable to use due to their low reliability |
| DVD | 3 | 3 | 3 | 1 | 1 | 3 | Not advisable to use due to their low reliability |
| Tape | 2 | 1 | 1 | 3 | 3 | 1 | Best choice due to their high reliability |
| External hard drive | 2 | 2 | 2 | 3 | 2 | 3 | If you are not using a tape backup, use this method |
| USB flash drive | 1 | 2 | 2 | 2 | 2 | 3 | Seem to experience failures over time, so not advisable to use |
| Online backup | 3 | 2 | 2 | 3 | 2 | 3 | If you choose this method, investigate any security concerns very carefully |
What files to backup
A general rule of thumb is if it cannot be reloaded from some other source, it should be backed up. This means that there is no reason to backup software or your operating system, which could be reinstalled from their original source. Documents, multimedia files, e-mail, downloads, and other files that cannot be recovered from an original source should be part of your backup strategy.
Disaster Planning
Hopefully you will never need to use your backup to recover files, but it pays to be prepared for this possibility. Create a plan that outlines the following points.
- Who needs to be notified in the event a recovery is necessary and how will they be notified?
- Who needs to be involved in the recovery effort?
- What is the expected recovery time?
- Will there be downtime required or can users still work on the system?
- How will verification that the recovery executed correctly be performed?
- What are the steps required to perform the actual recovery?
- Who needs to be notified once the recovery is complete and how will they be notified?
- What is the possible loss of data (i.e., data that was created after the last backup was performed), how will it be identified, and will it be necessary to recreate this information?