Many companies do have a backup strategy in place, but the next couple paragraphs will address the most common problem where those strategies go wrong.
If your organization has a large enough computer network, you already have a person specifically responsible for backup. These people typically have the right training and do a good job of planning and implementing backups. There is, however, one common mistake.
The annals of computer network administrators are full of good backup strategies gone bad with the absence of one basic element: testing. Make sure the backups work. Do a mock disaster and recover some “lost” files. Test your backups on a regular basis!
In smaller networks, those with 10 computers or less, backup strategies are not always so well defined. Here is some advice for protecting yourself from a great deal of frustration in the event you need to restore data from backups.
I have found that smaller organizations tend to have a more difficult time with a well structured network, especially since they usually cannot justify the expense of a network administrator. If large corporations need to be efficient in planning their networks, it is even more important for a smaller organization whose staff members usually divide their time into multiple roles.
My goal with this page is to be as brief as possible, yet complete enough to be useful in helping you understand computer backups. This is not a comprehensive textbook, nor do I want it to seem like one. It will tell you what you need to know to back up a small network, or a single computer, in a way you can actually comprehend.
Rather than launch right into a detailed backup plan, we need to start with some basic file structure advice. If you are running a network with more than 3 computers, it is strongly recommended that you get a network operating system. The tools you will need are built in and will save you time, plus it will reduce the growing pains as you try to get more efficient.
Regardless of your operating system and network configuration, you need to think in terms of file centralization. Fortunately, operating systems such as Windows XP tend to somewhat automate the task of centralizing files, but understanding these principles will help you plan a more efficient network. You want to avoid having multiple versions of the same file on your network so everyone accessing shared data is synchronized. You also want to be sure all your data files are being included in your regular backups.
These are some general guidelines. You will need to adapt these recommendations to your particular situation, but the principles here should be very helpful.
Everyone using the computers should have a folder of their own. Each user can organize their folder in a way that makes sense to them even if it makes no sense to anyone else. All of their work should be in that folder, and it can be divided into as many subfolders as needed. The backup plan should include backing up each user's folder, then you can be sure that all the data is getting properly backed up.
All of these user folders should also be inside of another folder on the main drive (the main drive is C: in most cases). I recommend you name that folder yourself, but you can put all the user folders inside of “My Documents.” Many software programs will go to the My Documents folder by default, so this is a simple method of centralizing user folders. This might raise some security issues, so I would recommend you read the Computer Security section also, to see if you are comfortable with using My Documents.
Next you want to centralize the shared data that everyone needs to have access to. The advice I am providing here is not intended to deal with all the security permissions or what level of access everyone has, only the fact that it needs to be centralized. When any changes are made to the shared data, everyone accessing it must be getting the same version. Having all this in a folder called “Data” is a simple method of centralization.
The goal is to have as few master folders as possible that contain data which changes frequently, and then to have everyone accessing the same files for the shared data. Your backup strategy will center mostly on data, so this will simplify the task of backing up. Avoid redundancy except in the backup process, which we will discuss below.
This practice also simplifies what could be the most practical part of your backup strategy. By keeping a special set of just the files in these folders and making regular updated backups, you can restore an important file that accidentally gets deleted or corrupted without having to weed through a full backup. If you plan on storing these backups on CD or DVD, be sure to read the short section below on computer backup media.
The principle of good documentation applies to every area of business, and your computer network is certainly no exception. Create a formal plan of how your file structure is organized. Seeing it visually will not only provide a guideline, it may reveal weaknesses, or inspire ideas for improvements.
Once you develop a file organization structure and backup strategy, keep good records so you can restore those backups with the least amount of downtime. Document everything, including your test schedule. Yes, you need to test it regularly!
Keeping all these records is not convenient, it can even be a nuisance, but if you will take the time to do it, you will be glad you did. Be warned, the opposite is also true!
Although it is possible to back up data using a CD burner, DVD burner, Zip® drive, Jazz® drive, or other means, these methods usually are not very practical. In most cases, you will want to get a magnetic tape drive specifically designed for backup. Talk to your office supply or computer supply dealer as these are easy to find.
One word of caution in selecting your media. Consider the “cost per megabyte” as less expensive drives may cost more for the tapes. Speed, capacity, and other performance features will also affect the cost. Buy what is appropriate for your needs and potential growth.
Magnetic tape media should be stored and handled very carefully. Transporting it offsite is risky since this is a delicate media. It should not be subjected to sudden movement, sunlight, temperature extremes, humidity, etc.
If you opt to use a CD or DVD as storage media for backups, I strongly recommend you still use backup software or zip compression (discussed below). If you simply make copies of your drive and burn them to CD or DVD, the copies will be automatically converted to Read Only format which cannot be modified. If you were to ever restore these files, you might find them very frustrating to use if you want to modify them. Not all operating systems convert these files back to their original format when you copy them from a CD or DVD back to your hard drive.
A simple method to protect against primary hard drive failure is to install a second hard drive for backup. This does not eliminate the need for additional storage media and offsite backup, but since hard drives are prone to fail easily, it provides quick and easy recovery if you ever experience a hard drive failure.
I am providing suggested resources at the bottom of this page for tools you will find useful in creating backups and/or simplifying zip compression.
The official term used is Grandfather-Father-Son, which generally refers to monthly, weekly, and daily backups. Your plan, and how often you make each kind of backup, can to be tailored to meet your needs.
Whenever you discuss computer backup, there is always the classic question, “How often should I back up?” To which there is the classic answer, “How much data can you afford to lose?”
If the advice given here begins to seem like overkill, maybe it is in your case. Just remember this simple fact, the people who know the most about computers trust them the least. They are backup fanatics and usually store their backups in multiple locations, onsite and offsite, with redundant duplicates. Ignorance is only bliss until you get jolted with a forced educational experience.
The benefit of the monthly, weekly, and daily backup scheme is that your computer can be fully restored even under the worst disaster, plus, your backups will cover an entire year. Your yearly cycle would require 12 tapes, one for each monthly backup. Each month, you back up the entire hard drive. That way you can be totally sure you have everything.
Your weekly backups would require 4 tapes that you systematically rotate, one for each week of the month. Do a full backup, then you have everything that has changed since your monthly backup. Hopefully, you will never actually need the monthly backup, but it is far better to be safe.
It is true that you could restore the entire computer by reinstalling all the software from the original disks. That would also require a huge investment in time. You have most likely created some settings that would need to be manually recreated. Remember how long it took you to get it all set up in the first place?
There is also the issue of file structure. In spite of your best efforts, some files, and especially program settings, end up in weird places. These could easily be missed if you don't perform full backups. Now you do plan on testing those backups, right?
The daily backups do not need to be full system backups. As you might have already guessed, most of the information on your computer does not change very often. For the most part, only the files you actually work on really change. Fortunately, your computer knows which ones those are, and there is a way to target only those files for daily backup. In the next section, I will show you how to understand that better.
Under most backup software, including the backup program built into all Microsoft Windows® operating systems, there are options to do a full backup, incremental backup, and a differential backup. Say what?!! If that isn't techie enough for you, I am also going to introduce you to something called an archive bit. Whoa!!
The archive bit is nothing more than an on/off switch for every file on your computer. When you do a full backup, they are all set to off. That simply tells your backup program that each file is backed up. When you make a change to a file, it flips the switch back on. Then you choose faster backup options that look for files with the trip switch on because they are the only ones that have changed since the last full backup. These options are explained below.
I would hope that you are now seeing the value of centralizing all the data files. Since data files are the ones that are most subject to change between backups, centralizing them greatly simplifies the process of backing up your information. As mentioned above, you can create regular copies of just the data files in the event you need to restore one that gets accidentally deleted or corrupted.
Now to help you understand those intimidating terms above without weighing you down with too many details.
A differential backup will look for all files that have changed since the most recent full backup. It does not reset the archive bits which means that in the event you need to restore all the data on your hard drive, it will be the easiest one to work with. You only need the full backup and the most recent differential backup, and voila, you are back in business.
An incremental backup is the easiest and fastest to create, but the hardest to restore data with. It resets the archive bits, which means it only has to back up what has changed since either the last full backup, or the most recent incremental backup. The drawback here is that if you need to restore your data, you would need the full backup, plus every incremental backup, and they must be restored in the same order they were created.
Put another way, let's say you do a full backup on Sunday while no one is in the office. Then you do daily backups each night, but on Friday your hard drive makes a weird noise and everything is gone. If you use differential backups, you put in Sunday's tape and Thursday's tape and you are done. If you use incremental backups, you need to put in Sunday's tape, then Monday's, then Tuesday's, then Wednesday's, then Thursday's, and in that order.
Since I am writing this information primarily to organizations with smaller networks, the built in backup program in your operating system is usually sufficient to create good backups. On a Windows® computer, click Start, then Programs, then Accessories, then System Tools, and Backup will be on the list.
Make all your selections for what to back up, where you are backing up to, and so on. Look for the Options or Advanced button/menu on the Backup utility to fine tune your backup, including the selection of Full, Differential, and Incremental backups.
You can also schedule backups to occur automatically. Click Start, then Programs, then Accessories, then System Tools, and select Scheduled Tasks. From the Scheduled Tasks window, double click on Add Scheduled Task. The Scheduled Task Wizard opens, click the next button and choose Backup from the list of applications and proceed through the rest of the wizard making the appropriate selections.
NOTE: Different versions of Windows may vary slightly from the instructions outlined above.
You should have multiple copies of backups. At least one copy should be stored offsite in the event of fire, theft, or another type of disaster. Also, if one copy fails, you still have another chance to avoid panic.
Make sure you have enough backup media to keep a safe rotation schedule and clearly label it. You would not want to accidentally overwrite this week's backup over last week's backup without being sure you could restore last week's just in case something was wrong with this week's backup (You catch all that?).
A good media rotation schedule is outlined above in the master backup plan section, It is called Grandfather-Father-Son.
Also as outlined in detail above, organize and centralize your files to make backup easier.
Develop a written plan as to how you will organize files, how your computer and/or network will be structured, and how backups will be implemented. Use charts, diagrams, or whatever is helpful in visualizing it and communicating the plan so all users understand it.
Make a schedule for backups. The responsibility for backup should be specifically delegated and arrangements should be made if the person responsible cannot be available for a scheduled backup.
Full backups are the most reliable method of being sure everything is included in the backup. These should be done often; for most businesses, about once a week.
Consider making a separate copy of just the data files in case you need to restore one file that is accidentally deleted or corrupted. Most backup software will allow you to restore a single file or folder.
By the way, did I mention that it is important you test those backups regularly?