Delta Computing
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Delta Computing
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Backup FAQ's
Backup Hardware Backups can be done to floppy disks, to tape drives or to large removable media such as CD/RW, Zip, Jaz or Orb drives. Depending on the amount of data you want to back up and the speed and frequency of the backup will determine which media to use. If you only have a small amount of data and back up infrequently floppy disks will do. If you have large amounts of data you will probably want to invest in something that will hold more data and backup more quickly. Floppies - Floppies are relatively inexpensive and you already have the device on your machine. However they hold less than 1 1/2 MB of data each and are very slow. Since most backup programs will compress data you can get approximately 2 1/2 MB of data per floppy and it will take about 2 minutes per disk. A backup of 10 - 15 MB of data will work fine on floppies. The other major disadvantage of floppies is reliability. Because they are open to the elements the possibility of damage to a disk is high. Tape Drives - Tape drives hold much larger amounts of data, anywhere from 250 MB to 25 GB. The capacities of tape drives are always expressed as compressed so their actual capacity uncompressed is half of the listed capacity. The less expensive drives are slow and have lower capacities. A 250 MB backup may take several hours to complete. Most tape drives have included software that will allow you to schedule a backup so that it can take place in the middle of the night so that you don't have to sit and wait for it. The more expensive tape drives using DAT (Digital Audio Tape) have larger capacities and faster speeds, they are also more reliable. A major disadvantage of all tape drives is that they are linear. If you need to restore a file that is at the end of the tape you have to wait while the tape advances to the area where the file is located. This can take a considerable amount of time with a large tape. It has also been my experience with low end tape drives that they are not altogether reliable. Your careful backup proceedure is rendered useless if the backup cannot be read. Removable Media CD/DVD - There are a number of different removable media systems available today. CD/R (CD Recordable) CD/RW (CD Rewritable) is a CDROM drive that will allow you to create your own CD's. The advantage of CD/R is that it is permanent. A CD will last for 75 years or so. CD/R can only write once to a disk. The disks are inexpensive (under $1) and most drives can write fairly quickly. A CD will hold 650 MB uncompressed so with compression you can probably put a GB on a single disk. CD/RW has the same disk capacity but the disks can be erased and overwritten. The blank disks are more expensive ($1 to $2) but because they can be reused many times they can be cheaper. The down side to writing CD's is that they are a linear write. This means that the disk is one continuous track (sort of long a record - remember those?) and if anything interrupts the write you are left with a mini frisbee or drink coaster. Despite the claimed write speed of your CD writer you may not be able to utilize the full speed. Be sure to buy disks that are rated for the speed you are going to use. Sometimes trial and error is the only way to determine the fastest speed possible on your system. DVD writers are similar to CD writers but the capacity is greater, about 4.5 gigabytes. There are some new drives being developed using advanced technologies that may provide up to 27 GB. Removable Disks - There are a number of removable disk options. Zip disks come in 100, 250 and 750 MB versions. Jaz drives come in 1 and 2 GB versions. Syquest has a 1.5 GB drive and Orb is a 2.2 GB disk. All of these capacities are uncompressed. All of these feature a disk similar to a floppy which can be inserted, written to and removed. Like a floppy they can be overwritten many times. They can also be considerably faster than most other methods of backup. Because they are random access devices restores are very quick as well. Most of these devices come as either internal or external versions. The advantage to an external version is that you can move it from one machine to another so you can back up or transfer information on more than one computer. The external drives are considerably slower than the internal drives however. If all your machines will support USB (Universal Serial Bus) that is far faster than a parallel port version. Furthermore the parallel port versions plug in where your printer attaches to the computer and then you attach your printer to the external drive. This occasionally interferes with the proper operation of the printer. Some of these external devices also come in a SCSI (Small Computer Systems Interface pronounced scuzzy) version. This requires an extra card to be installed in your computer but it offers very high speed communications. Zip drives start at about $90 and a SCSI Jaz drive can run as high as $500. Media for these drives ranges from less than $10 for a Zip 100 disk to as much as $120 for a 2 GB Jaz disk. All of these drives offer high capacity for relatively low cost. External Hard Drives - These are becoming a viable backup option. They are available in any size hard drive currently available (up to 250 GB.) They usually connect via USB 2.0 or Firewire (IEEE1394) and they are fast and convenient The downside to them is that they don't have removable media, in order to have your backup off site you must take the whole device with you. Why Back Up? There are many reasons to back up your computer. The most obvious answer is to protect your data but it goes beyond that. Protect it from what? The most obvious reason for a backup is the failure of your hard drive. The phrase computer experts use is "It's not is your hard drive going to fail but when is it going to fail." Other reasons to back up include accidental erasure of a file, accidentally overwriting a file, damage due to virus attacks, a need to make archive copies for future review or physical destruction or loss of your computer due to fire, flood or theft. The type of backup you do depends on how quickly you need to get back up and running. A data only backup will help you if you have lost individual data files. The advantage to data only backups is that they are smaller, quicker and easier to do. No backup policy works if you don't do the backups because they are too cumbersome or slow. A full system backup backs up everything on your drive. This allows you to quickly restore your system to full working order. The disadvantage is that with today's systems this may require a backup of 2 to 10 GB or more. How Often to Back Up? Let your own level of fear be your guide. Generally I recommend that you back up as often as you have done enough work that you don't want to do over. This could be daily, weekly or monthly depending on your use. Whatever the interval is you should develop a routine and stick to it. Some programs such as accounting software come with their own backup programs built in. I recommend that you use these every time you do any significant amount of work. How to Back Up When backing up you have a choice of different types of backups. The simplest is just copying files to a removable device of some sort. This requires no programs, settings or schedules. Just copy the files whenever you want them backed up. The next level is to use a backup program, either one that comes with Windows or your device or that you have purchased. Then you need to decide whether to do a data backup or a system backup. Once you have done a backup you can choose to do an incremental backup. This only backs up files which have changed since your last backup. These files are stored in a different set. Since you are only backing up changed files the backups are usually small and fast. Because each backup only contains some of the files, however, you may have to search through many backup sets to find the file you want to restore. Compression is another issue. If you compress your files you can get more data on a disk. However you frequently have to use the same version of the same program to restore your files in the event of a catastrophic system loss. This means that restoring your Windows95 files on your new Windows ME computer may not work. Important Tip: Whenever you make a backup you must be sure that all programs and files are closed. If you leave data files open they will not be backed up. When making backups it is a good idea to use two or three sets of media. What this means is that on Monday I backup to disk set 1, on Tuesday to set 2, on Wednesday to set 3 and on Thursday back to set 1. The reasons for this type of backup is that you may have unreadable media in a backup set or the file may have been damaged prior to being backed up. If your media are unreadable you effectively have no backup so having an earlier set lets you get back most of your data. If you have backed up a damaged file an earlier backup may have a good copy. While either of these problems may cause some data to be lost it is much better than all data being lost. Your backups should be kept in a safe place. Since one possible loss of your data is physical destruction of the location where your computer is located, having a backup in that same location will cause it to be lost as well. Either a fireproof safe on premise or an off premise location is a good idea for storing your backups. If you are doing a data only backup be sure to get all the files you might need. People often forget the files that contain their address books, e-mail or password lists. Find out the name and location of all the data files that you use so that you can include them in your data backup. Compare Most backup software allows you to compare the backup to the original files. It is strongly recommended that you do this, at least periodically. Since backup media is removable it is subject to damage. I have seen people who have religiously backed up their data being unaware that they were wasting their time because the backup media was damaged. If you are doing a scheduled backup overnight it won't delay you to add a compare every time you back up. Archive Sets Archive sets are a good idea. Periodically you should make a copy of your data and store it permanently. This allows you at some future date to recover files that you have erased from your computer as unnecessary that you may find you need years later. CD's are an especially good way to do this type of backup. Other Backup Technologies A number of new technologies are starting to appear. These are backup services which allow you to backup your files onto their computers via the internet or by modem. Many of these services actually store your data on several computers located in different parts of the country to survive a disaster in one part of the country. The advantage of these services is that they allow you to access your data from anywhere at anytime by providing the correct password. This allows you to get back that important proposal that you are going to present out of town when your laptop loses it. Prices for these services vary depending on the level of service provided. There are free internet services with limited capacity up to very secure high speed systems costing $100's or $1000's per month.
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. What is the best way to back up my
computer? 
. There is no best way to back up a
computer because everyone has a different need and capability for backup. Some
people just back up their data while others back up their entire system. Lets
look at some of the ways and methods to backup.
