 The magazine of the Melbourne PC User Group Beginners' Bytes: Part 8 Ron Wilby |
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Welcome again to all you beginners and to all the experts among our readers. This month we'll talk about backups and backup strategies.
Backups
By now many of you are thinking "Ron is a Backup Fanatic. We don't need to bother with all that stuff, we'll just backup the files we used today onto some old floppy." Well, I've been there and done that. I lost all my files and it took me a lot of work and a lot of time to get things going again. One day you'll need a proper backup, and you'll need it very badly. I had a lady on the phone recently who runs a secretarial business. She keeps all her customers' records on single floppies, one customer, one floppy. Of course I was horrified and tried to explain why. She didn't seem convinced, but she will be when someone puts the phone or some other magnetic device on one of those disks and she has to explain to her customer.
Doug Brooke describes a "Backup" as what is required to get you going after a disaster. This involves having a "disaster recovery disk," a necessity that many utility programs will help you to make. Parts two and three of this series discussed disaster or "panic" disks in some detail.
Be sure that you are able to recover by making two of these disks, putting one in a place away from the computer. Be prepared for the situation where your computer has gone, and all you have left is your backup and, I hope, a cheque from the insurance company.
Disk or Tape Backups
A narrower meaning for "Backup" is a set of disks or tapes containing all the data and programs that normally reside on your hard disk. You should have a disaster recovery disk, a full backup of your data and programs and a virus scan and clean up facility.
Earlier versions of DOS had a Backup and Restore facility which I have never used. It had an evil reputation and I have seen the disastrous results of other people's attempts to use it. However, I note that DOS 6.0 has a new backup utility, with software licensed from Symantec's Norton Division. Perhaps Microsoft was no happier with the old Backup and Restore than their customers were. So, those of you who upgrade to DOS 6.2 can use this new feature. If not, Norton Desktop or PC Tools each include well-tested backup utilities. These programs (collections or suites of programs actually) are not cheap, being in the $200-$300 region. However, they do many things in addition to backups and are well worth considering for their general usefulness. Also, the backup programs can be purchased separately, the PC Tools version under the name of CP Backup.
Tape Drive Backup
An alternative not to be lightly dismissed is a tape backup drive. The cost isn't as bad as you may think. Increasingly large Application programs, and the increasingly large hard disks they demand are going to need large quantities of backup floppies.
Of course, I know you don't need to back up your programs, only your data, but this is not strictly true. All of us tend to "customise" our Application programs somewhat, and therefore we need a complete backup. For example, a while back I accidentally returned all the colours on my wordprocessor to the original default values. Those colours are awful, and without a backup it would have taken me hours of fiddling to get back to "my" colours.
Thus the tape drive may actually be cheaper, and it's a lot easier to use. The cost of the tapes, which are called data cartridges, is about one third the cost of floppies of the same capacity. You set the tape running and go off for a coffee (or a nightcap). When you come back it's all finished. Your only real alternative is no backup at all, in which case I suggest psychiatric help is needed, now or later.
The Archive Bit
The archive bit is a special status bit contained in the directory entry for every file on your hard disk. This bit is used to decide if a file has been changed since it was last backed up. When a file is changed or created, DOS "sets" the archive bit, so that your backup program knows which files have been changed since the last time it was used.
Backup Methods
Both Norton and PC Tools offer various backup methods. The facilities offered by PC Tools' CP Backup include Full, Full Copy, Incremental and Differential backups. You can back up to disks or tape. Let's explain the meaning of the above terms.
Full backup means everything on your hard disk. The archive bits of all files are "cleared," which marks them as having been backed up. Full Copy is the same as Full except that the archive bits are not changed. It is used to make a copy of your hard disk's contents without changing the archive bits.
Incremental is a partial backup containing only those files which have been changed or created. Thus, the incremental backup files can be appended to the last full backup.
Differential is a different form of partial backup used where large files are changed frequently.
Backup Strategies
Until recently, by being pretty ruthless with my hard disk files, I had only about 30 MB in use. Then, my strategy was to do a full backup (all files on my hard disk) every Friday night. I used two sets of backup disks, used on alternate weeks so that I didn't overwrite my last backup. Backup was to 1.2 MB floppies and I verified the backup data. I needed about twenty floppies and the process took about 25 minutes. I stored my last week's backup in my garage, a fireproof brick building offering reasonable safety. Then I did an incremental backup every night at knock-off time usually on only one disk, so I had two sets of incremental disks labelled Saturday, Sunday etc. Whatever backup method you use, restore one or two directories to make sure your backup really works. Check that the restored files will actually run the program.
Never, never, write over your last backup.
Have two or more sets of backup disks. Make set A this week, set B next week, then if it turns out that set B is virus contaminated or otherwise corrupted, you can always go back a week. You will lose some data but not too much. I am now using a similar strategy with my tape drive. I do a full backup tape on Friday night, then from Saturday through Thursday I do incremental backups to another tape. Then when Friday comes around again, I do a total backup to a third tape which I store in the garage. Since the data cassette normally used has a capacity of 120 MB, you can do full backups much more easily and quickly than with floppies.
Unfragmenting
When you are working on a file repeatedly, DOS is not able to join your latest work exactly onto the end of what you did yesterday, because there is probably not enough room. DOS therefore writes the file in sections, which are scattered all over your hard disk. When you tell DOS to find the file, it may have to search for fifty or more fragments and put them together. This naturally slows the operation of your system. To find how bad the problem is, type CHKDSK * . * when in the root directory.
Norton Utilities or PC Tools have programs to fix this problem and it is worth running them once a week or so. Some of these defragmenters are called "optimisers." I use a program from Mace Utilities called UNFRAG. Takes ten minutes, nice time for a coffee or whatever you have late at night. DOS 6.0 and 6.2 have a defragmenter included.
What Hardware Do I Use?
A question I am often asked! The answer is: A "Total Peripherals" 286-16 that never missed a beat has now been upgraded to a 486DX with 4 MB of RAM. Very good, solved my memory problems which were a worry to me. I've recently acquired a 3.5-inch floppy drive, a 250 MB hard disk and a Colorado tape backup drive. My colour monitor is an NEC Multisync 3D, four years old but a delight to use still. A "built like a battleship" Canon PW1080 printer that came with my first XT, churns out thousands of labels and other items. Lacks the facilities of modern printers, but very reliable-you can start it on a 4-hour job and go shopping-when you get home it will have finished your task. Many printers jam five minutes after you close the door and go out.
The software is all legal. WordStar 6.0, Lotus 1-2-3, Paradox and Quattro Pro are my main programs, with Quicken to take care of the finances and Grammatik 5.0 to tidy up such pieces as the one you are reading. A word of warning. If you use professional software, you will continually receive "upgrade offers." These usually come in the form of brightly coloured, tempting brochures highlighting all the "enhancements" the new version offers. There are two snags here. First, you have to part with some money (sometimes of the order of $200) to get the "upgrade kit." Worse, when you get it, you start a whole new learning experience that will take you many hours of your valuable computing time. Consider carefully whether the upgrade is worth while. You can successfully write letters on a word processor that has had several revisions since you bought it.
Utilities
Here I define utilities as groups or "suites" of programs which come under a common name. Examples are PC Tools, Norton Utilities, Norton Commander, Norton Desktop and many others.
PC Tools for example includes a DOS Shell file manager, Desktop Manager, Data Recovery, Hard Disk Backup, Windows Utilities and virus protection. This brief description hardly reveals the extent of the programs, which come with eight manuals and seventeen floppy disks (for my now outdated v7.1). See what I mean about a learning experience? This may sound complex, and it can be, but one of these utilities groups would be a good investment for many of you. Save up, go to the software dealers and find out which one will suit you.
An extremely valuable tool is Vernon Buerg's LIST, obtainable from our Shareware library. Doug Brooke says "I couldn't live without LIST." It is described as a "File Browsing Utility" and be assured it can do many things that no other program can match.
Parking
Two minor items to close this month's episode. Some of you may have hard disks that require the heads to be "parked" before you turn off the power. Parking moves the heads away from the delicate data containing disk surface so that no damage can occur. Larger and more modern hard disks may not need this, but you should check your particular drive or play it safe and park it nevertheless.
Surge Suppressors
Second, a surge suppressor between the power point and your computer is essential and may cost as little as $20. Advice on these suppressors is available from our local Electricity Supply (City of Box Hill) and presumably from other authorities such as SEC. Buy yourself one, and one for the printer too, else a thunderstorm will get you soon!
That's it for this month, folks. Till next month .
Reprinted from the May 1994 issue of PC Update, the magazine of Melbourne PC User Group, Australia
