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Christopher Spry

Disk cloning: My suggestions for anticipating and dealing with a system hard disk failure

This page was written by Christopher Spry. I have been trying to promote among my friends the idea of always having at least two disks in computers: a systems disk and a backup of the system disk. I remember trying to get IBM to do this with the early PS/2 computers in 1987. It has never appealed to computer retailers and disk manufacturers have not exploited a potentially significant marketing strategy. I could not think of a better way to insure against a catastrophic failure of the system disk. I have used the 'two disks' approach on my IRIX Indy, Solaris and Windows workstation and notebook computers for several years. It has paid off handsomely when I had three system disk failures (dead disks) in a short period. I have just had failures of two system drives after having none for five years. In each case I was up and running again in about ten minutes, using the cloned system drive. PCs can have a removable drive in one of the 3.5" slots, for this purpose and for swapping in additional hard disk space if I need it.

There is a range of software to copy system disks under Windows. Symantec's 'Ghost 2003' backup software and PowerQuest's 'Drive Image' v 7.0.1 can handle DOS, Windows 95/NT/2000/XP, LINUX, and other partitions, even when mixed on the same hard disk. They can prepare an 'exact' copy of a hard disk or make a 'disk image' to a file on the same or a networked computer. I keep several image files, going back a month or so, of each computer's system drive. Note that Drive Image 2002 has proved preferable to Drive Image 7.0.1, to backup Windows 2000 computers, in my hands.

If your BIOS allows you to alter the boot sequence, it is possible to 'test' the backup very easily. (In my view, a backup is not complete until it has been shown to be able to 'restore'). Down time is a problem when doing the system disk backups with software that requires you to boot with a floppy disk or CD. I can not see a way round this other than doing it at less busy times of day. However, the alternative of wasted hours while a new system disk is made, after a crash, is more than compensated for by short interruptions (say, up to 1.5 hours) while a full system disk is prepared.

In addition (or if you can not both boot a computer with a floppy drive and have a second hard disk in the system at the same time) you can use either of these backup programs to prepare 'images' of a system disk as compressed files on a networked computer. The disk 'image' can then be copied back to a new system disk, after a failure. Now that hard disks are cheaper and with a larger capacity than a few years ago, I have begun to make these images of the system drives on my computers. I store them on a 120-GB hard disk, which is always available on the network, so that it is easy to update the images. If this backup process is satisfactory, I may restrict making replacement  system disks to my principal computers.

I prefer to backup 'user' files (files generated by users of the computer), once or twice a day, to hard disks in a different location in case of fire or theft or damage. For that I use FileSync v 1.54, from Windsor Software. This synchronizes files and directories while running in a DOS window running under Windows. CmdSync v 1.0, a 'batch mode' version which is particularly useful for updating files across networks. It can ignore a two second time signature difference that can confuse other backup software, so that identical files are not copied between UNIX and Windows systems. I also occasionally write CDs with 'user' files and store the CDs on another site.

Since November 2003, I have been using Apricorn's hardware and software to make bootable clones of my notebook computers' system drives, which are otherwise difficult to clone. I have already used successfully a backup drive made this way, in a system with a failed system disk. I am using Apricorn's Hi-Speed USB 2.0 CardBus Card Adapter to speed the transfer of files in my notebook computers that only have USB 1.1. They can be bought from  California Peripherals & Components, Inc. The backup drives can be tested be booting with them, once the backup is complete.

I have suggestions on how to copy disks under IRIX and Solaris.

I am looking into the possibility of using serial ATA drives to record bootable images of Windows computers. The reason for this is that the backup time would be much shorter than using other current methods, see CMS, who have begun (February 2004) to sell software and hardware to do this.

Other backup software programs include Second Copy 2000, Acronis TrueImage, BackUp MyPC, AISBackup and e-Backup.

Since March 2005, I have been using Buffalo 'TeraStation' 1-GB network attached storage, to make full 'images' and daily incremental backups of my PCs using  Acronis 'True Image 8.0 Corporate Workstation'. I have information on this web on how to do this.

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