Article:		Automated Backups with Existing Tools
Subject:		Compression?
Date:		2004-02-15 17:22:05
From:		lonney
I'm going to get a firewire disk soon for backups of my shiny new PowerBook 12" DVI (its my first apple and I love it to bits) Nice article, I recently asked this question on IRC in one of the Mac channels but the answer was just to be lazy and use CCC. This is good, its nice and simple. just what I was after. Are disk images compressed? if not is it possible to compress them and still work with them in the same way?

Showing messages 1 through 3 of 3.

• Compression?
  2004-02-16 15:05:06  peterhickman [Reply | View]
  
  
  By default the images created are compressed but as my script creates a blank image of a fixed size first the compression is to no avail. However as you may have seen suggested in the feedback there is another way of creating an image. Keep lines 1 to 11 of my origonal script, delete the rest and then add the following line.
  
  hdiutil create -srcfolder $SOURCE -fs HFS+ -volname $VOLUMENAME $IMAGENAME
  
  If you hold on for 24 hours I am testing this and will tell you how it goes but I don't expect it will be amazingly smaller (but we shall see) but it should be quicker.
  
  And you should be able to use the resulting image files in the same way as before.
• Compression?
  2004-02-16 23:57:40  peterhickman [Reply | View]
  
  
  I take that back, it does indeed compress well my 11Gb went down to 5.5Gb. However, and there is always one, the backup took longer, almost twice as long, and the image file takes a damn long time to mount.
  
  Presumably uncompressing a 5Gb image takes some time.
• Compression?
  2004-02-17 23:02:02  lonney [Reply | View]
  
  
  Cool thanks for that.