Why should I backup my files?

The answer is simple, for the safety of your files. No one is infallible, and no system is fully safe from disk damage or virus attacks. I mean, how many times have you deleted or changed files, only to find that you have made a monumental mistake, and wished you could have brought the old version back again, or you erased the wrong disk by mistake. Backups are essential for important data, don’t leave it until it’s too late!

Different kinds of backup strategies

A backup strategy is basically a scheme that you use to repeat over a given time, be it all the time or for a set period of time. This includes: whether you want to rotate your media or not; type of media to use; and most importantly how often you wish to do a backup. All of these actions revolve round full and incremental backups.

There are a number of different backup strategies that you can employ, all vary with how often you want to backup and onto what media you plan to backup to. I can suggest about 3 strategies to use, how often you want to backup depends entirely on you, this reflects on how often you modify your data:

A full backup is where you essentially, do a copy of all the files in a given location or a disk. While an incremental backup adds any modified or newly created files, in the selected folders/disks, to the full backup set.

Rotational backups means that you use a number of backup 'sets' (sets of disks/tapes that make up a single backup), and when the next backup is required, the oldest 'set' is overwritten. Normally, anything from 3 to 10 backup sets are used, depending on the amount of data to backup and the whether you want to do incrementals to it - this dictates the number of disks or tapes that you need for the backup, and over what time period it covers the data. This backup strategy is useful if most of the data backed up is always modified, and therefore you need to backup per day. This is recommended for big businesses with huge amounts of data to backup.

Full Backups Only - This means that you do not intend to do incremental backups to the full backup set. Only useful if 75-100% of the data is modified/added very regularly, and therefore incremetal backups would take up too much disk/tape space. Suggest you do this type of backup every day or set number of days.

One Time Backups - Often refered to as archiving jobs/data to a central source, where it is very unlikely to be changed in any way. This type of backup is usually duplicated, and kept off site, for safety reasons.
Don’t forget the stuff on your desktop, although you should really keep important data in a folder on the hard disk, not on the Desktop, which is a special folder located on each hard disk or partition and you may forget to back this up.

Three examples and commonly used strategies to use (that I know of):
1) Strategy 1 - A full backup every XX days/weeks/months, with no incremental backups.
2) Strategy 2 - A full backup every XX weeks/months, with incremental backups every XX hours/days thereafter for XX number of months or a full year.
3) Strategy 3 (recommended) - A full backup every XX weeks/months, with incremental backups every XX hours/days there after until another full backup is required because the current backup media is nearly full.

Important note: Always make sure that when you’ve done a full backup, that the data is not corrupted, especially when the program uses compression. You can easily check this by restoring some of the files throughout the length of the backup set. Then use a program to load the files, to see if they’re OK or not. This check is highly recommended when you wish to either reformat your hard disk or transfer the data to another computer.

Another important note: When using an archive backup program such as Retrospect, you must keep a backup copy of the catalogue file on another disk, so that if and when disaster strikes, or you just need to reformat the hard disk, it is always to hand - as it is easier to just reinstate the catalogue file than it is to rebuild the catalogue. You should also update this backup copy whenever you do incremental backups as well.

Backup methods

Here are three kinds of backup programs that you can use...

1) Manual Backup - You manually copy files to a separate hard disk, or CD-R.
Upside: Extremely convenient way of backing up, done at your leisure.
Downside: It is also the most susceptible strategy for virus attacks and drive/disk failure and user error. Depends heavily on the user knowing what to backup. This is a very primitive backup method, and is only for those on a very tight budget.

2) Synchronized Backup - This is one up from a manual backup, because this time the synchronization of your data is kept exactly the same as what is on your main hard disk, and the application does it automatically, ruling out user error.
Upside: It is very easy to do this type of backup, and very convenient, because you can syncronize your backup to any mounted volume or partitions.
Downside: However, this method is still prone to disk corruption and virus attacks, as the synchronization app invariably needs the backup volume to be connected most of the time. As the files are still a direct copy of the ones on your main hard disk, they are only a good as the ones on the original hard disk. If any file that is corrupt or deleted accidentally before the sync is completed, you will lose both copies. You can buy shareware or commercial programs that do this type of backup for a modest fee.

3) Archive Backup - This is the most effective and efficient way to backup your data.
Upside: It compresses your data, saving disk/tape space. All backups are archived, and therefore it cannot be attacked by viruses or be deleted. It allows multiple copies of the same files tobe stored in the same backup set. It is usually stored away from the main system and often in a different building, therefore corruption of the disks or tapes is kept to an absolute minimum.
Downside: The software is quite expensive (£100 or more), and you probably need to buy large capacity media or drive to backup to.

Remember, do not store magnetic media (floppy disks, hard disks) near a magnetic source, eg. a magnet, as this will eventually erase everything on the disk.

BACKUP TIPS

What should I backup?

First and foremost is your data, then possibly the system files and installed applications. However you may not need to bother with those, especially with MacOS X as there is so much of it, and you will probably have to use the installation disk to get it into a bootable state anyhow. Although Dantz’s Retrospect Backup program can restore a whole system disk back to a bootable state, but you need version 5.1 or 6.0 to do it.

You have to ask yourself one question, what files can I live without if my hard disk is totally wiped? Then you need to sort out what folders or disks you need to backup.

Organise your data before a backup

Before you do a full backup I suggest you do a some reorganisation of your data, by putting them in folders and just backup a few folders instead of the entire hard disk, because the backup program will copy the Desktop DB and DF files along with half a dozen other useless and varying size files as well. This will make it easier for you when you setup the backup program for future incremental backups etc., and unnecessary files will not be wasting valuable disk space.

You might as well do a bit of house cleaning of your files, before you do a backup, as well. Just delete any files (especially large files) that you don’t want, or even move any files that you don’t want to backup, by placing them into other folders or disks that are not backed up.

How often should I backup?

Depends on you really. If it’s just ordinary personal data, then once a week should suffice. However if the data is very important or a lot of work has gone into them, and those files get modified/created daily on your hard disk, then you should back it up every day, or even every 12 hours. Personally I backup my stuff every weekend, but that is just personal data, and I don’t modify or add many files to my hard disk anyhow. Of course it’s entirely up to you, how often you want to backup your files.

The time you elect to do regular backups will reflect on the strategy you go for, even if it is only a temporary period of rush jobs. This especially goes for people who are self employed or a large business. But be warned, if you create and delete files in between backups, it will not get backed up, so, if you want to keep files to one side, leave in on you hard disk until the next backup copies it, then delete it. Remember to be mindful of your backup routine, and plan what you want to backup next time round.

Rotated backup sets

You should also consider having rotated backup sets*, or in other words a number of ‘generations’ of full backups (along with the incremental backups), so that you’re not relying on just one backup all the time. This gives you something to fall back on, so, if you accidentally deleted a file before the next full backup was done, you could go back to a previous backup and retrieve the file(s). I would say about 3 generations of backups is a minimum, and anything up to say 4-6 generations would cover an adequate amount of time, before you can erase the oldest backup set (this is the rotation bit), in preparation for a new full backup.

*A set consists XX number of disks or tapes used to make the backup.

What media to use?

It depends on what you can afford. The most common drive to use is another hard disk, however I do not recommend this as a main backup device, as it is prone to virus attacks, drive failure (constant use), directory corruption and user mistakes - especially if you have it connected all the time. The other popular drive/disk format is CD-R/CD-RW, which is better than a hard disk because your backups are not continuously connected to the computer and will never fall prey to virus attacks and accidental deletion of files, applies to CD-R disks only. However you can go for higher capacity drives, such as DVD-+R/RW or DVD-RAM which can hold upto 9.4gig of data per disk. The ultimate backup device is a tape drive, which holds tens of gigabytes of data, depending on the make and model.

What backup programs are there for MacOS X?

You'll find these programs either off the internet or in your local Mac shop. You'll also find that most of the syncronization backup apps are shareware, and nearly all of the archive backup applications can be purchased.

Archive Backup Programs
Archive backup programs store the files in a large file on disk or tape. This method allows you to keep old versions of files, and even deleted files or programs.
• PresSTORE Backup - from JPY plc (www.jpy.co.uk).
• Backup Mastery - from Charismac (www.charismac.com).
• BRU: LE/Desktop/Workstation/Server - from Tolis Group (www.tolisgroup.com).
• ES-Backup - from UGSoft (www.ugsoft.de).
• Impression - from I Need Your Software (www.ineedyoursoftware.com).
• Integrity - from Avail Solutions (no longer available).
• Retrospect Express/Retrospect - from EMC-Insignia (www.emcinsignia.com). Note that Retrospect Express is an OEM product, meant to be packaged with drives.
• SpeedTools: QuickBack feature from Intech Software (www.speedtools.com), plus it does syncronised backups.

Synchronize Backup Programs
Synchronize backup programs simply copy files to another hard disk or a removable/mounted disk. Except, you can access the files immediately via the finder - great for doing simple backups.

Freeware
• BasicBackup - from Hillman Minx (www.hillmanminx.net).
• Carbon Copy Cloner - from Mike Bombich (software.bombich.com/ccc.html).
• Drag'nBackX - from Enterprise Software (www.versiontracker.com).
• iBackup - from Grapefruit (www.grapefruit.ch/ibackup).
• iMsafe - from Sweetsoft (homepage.mac.com/sweetcocoa/).
• PsyncX - from Perforce Soft (sourceforge.net/projects/psyncx).
• Rsyncbackup - from Andres Akre Solberg (www.versiontracker.com).
• SilverKeeper - from Lacie (www.lacie.com/products/product.htm?id=10059).

Shareware
• Gemini - from Alan Poon (www.versiontracker.com).
• Revival - from Revival Software (www.versiontracker.com).
• MimMac - from Ascendant Software (www.ascendantsoft.com).
• Snyk - from Decimus (www.decimus.net/synk/).

Commercial (below $50)
• ChronoSync - from eCon Technologies (www.econtechnologies.com).
• Deja Vu - from Propaganda Productions (propagandaprod.com).
• FoldersSynchronizer - from SoftoBe (www.softobe.com).
• Synchronize! - from QDEA (www.qdea.com).
• Synchronize! Plus - from QDEA (www.qdea.com).
• Tri-Backup - from Tri-Edre (www.tri-edre.com).

Commercial ($50-$200)
• Data Backup - from ProSoft Engineering Inc. (www.prosofteng.com).
• Personal Backup - from Intego (www.intego.com).
• SpeedTools; Quick Back - from Intech Software (www.speedtools.com).
• Synchronize Pro X - from QDEA (www.qdea.com).

Specialised Backup Programs
• Apple Backup - from Apple (www.apple.com). For .mac members only - not very reliable.
• Carbon Copy Cloner - Mike Bombich (www.versiontracker.com). Duplicates the OS X system folders and anything else, duplication to another partition or disk.
• DV Backup - from CoolaToola (www.coolatoola.com). Allows backup onto MiniDV, Video8, or Hi8 video tape - 16.5GB per tape.
• SuperDooper! - from Shirt Pocket (www.shirt-pocket.com). Does the same as CCC above.