Symantec 10024709 User Manual

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Image file options
About Norton Ghost image files
About Norton Ghost image files
The image files created with Norton Ghost have a .gho or .ghs extension by 
default. They contain the entire disk or partitions of the disk. Image files support 
the following:
Various levels of compression
CRC32 data integrity checking
Splitting of media files
Spanning across volumes
Norton Ghost images contain only the actual data on a disk. If you have a 9 GB 
drive with only 600 MB of data, the Norton Ghost image is approximately 600 
MB, and is smaller if you use compression.
If you also use the Ghost Explorer application, an image file companion utility, 
you can recover individual files selectively from these image files without 
restoring the complete disk or partition.
Image files and compression
Image files created in Norton Ghost support several levels of data compression. 
When Norton Ghost is in interactive mode, three compression options are 
available: none, fast, and high. The Norton Ghost command-line switch -z 
provides access to nine levels of compression. 
As a rule, the more compression you use, the slower Norton Ghost operates. 
However, compression can improve speed when there is a data transfer 
bottleneck. There is a big difference in speed between high compression and no 
compression when creating an image file on a local disk. Over a network 
connection, fast compression is often as fast as, or faster than, no compression. 
Over a parallel cable, high compression is often faster than no compression 
because fewer bytes are sent over the cable. Decompression of high-compressed 
images is much faster than the original compression. The level of compression 
that you select depends on your individual requirements.