incremental backups

Dell / INSPIRION
June 27, 2009 at 02:08:19
Specs: Windows XP, 2Gb
If you do incremental backups does that rely on your NOT defragmenting your hard drive?
If you defrag, would the next backup have to be a full image?

See More: incremental backups

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#1
June 27, 2009 at 04:16:48
That is a good question that I have never thought about. I believe the type of imaging you would be using would not be affected by any defragging.

A raw image might be, but I don't think there is any such thing as an incremental raw image.

Programs like Acronis True Image realize that defragging is a normal part of computer maintenance.

Actually, you can restore an image made by Ghost or Acronis to a different drive/partition of different size/geometry.

Look at the link below for some additional info on the types of imaging.

http://www.disk-image.net/image_typ...


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#2
June 27, 2009 at 04:28:55
But surely when you backup the entire drive including registries, program files, etc. it's a sector by sector image?
I guess the fact that my backup is 21Gb instead of the drive's 50Gb capacity shows that it's not a full sector copy.

On another note, I have a trial copy of Acronis - will creating DVD sized 4.7Gb span files be okay or does the restore program work from DOS?


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#3
June 27, 2009 at 05:51:30
Did you read the information in the link I provided. Sector by sector copy will copy everything, including empty sectors. As you pointed out above the size will match the partition size and not be smaller.

I really don't understand the use of a raw image but there must be one. Ghost and Acronis default to imaging only the data.

I assume the way the data is compressed is to use more of the slack space in each cluster. Somehow that data has to be tracked so you know how to properly reassemble it. So there is some overhead involved.

I am not sure about your file size above. I will tell you that you should be able to span multiple disks and that typically Windows OS files will compress about a third. So you should be able to get over 6GB of compressed data on one DVDR.

Just make a trial run. I buy single layer DVDR on sale for about 15 cents each in spindles of 50 or 100. At that price I don't worry about the use.

I use Ghost 2003 and have multiple partitions on my main hard drive. Each is imaged at different intervals. I have used both DVDR and CDR on the same image with no adverse affects. Ghost simply accepts whatever type of media you supply. I am not a fan of rewritable media. To expensive and many optical drives may have trouble booting to them.

As I stated before, DVDR is actually only about 4.4GB of actual storage space. The numbers vary slightly depending on weather the disk is DVDR+ or-.


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Related Solutions

#4
June 27, 2009 at 12:42:55
Found this in the help files:
Note
• If you have defragmented your hard disk since the last full backup, an incremental backup could be as large as a full one. Therefore we recommend you to defragment the hard disk before the full backup of the given disk is created.

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#5
June 27, 2009 at 12:51:50
ignore, answered my own question. Obviously Acronis help files.

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