Symantec GHOST IMAGING FOUNDATION 7.1, Manual

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When you use Symantec Ghost across a network, use the fast compression option.
If disk space is at a premium, you can use higher compression, but it can affect
speed. The fastest performance over a network is usually achieved with
GhostCasting.
Using a 10 MB/second Ethernet network, a 25-60 MB/minute server speed is
common.
The following factors influence this range:
■
Using up-to-date drivers
■
LAN traffic
■
Choice of network hubs or switches, including brand and model
■
Compression
On a 100 MB/second Ethernet network, it is possible to achieve 80-300 MB/minute
under ideal conditions. This speed is influenced by computer hardware and LAN
performance. Greater performance is achieved with faster computers, NICs, and
hard disks.
Image files and CRC32
Cyclic Redundancy Checking (CRC) is a data error checking technique. CRC ensures
that the original data written to the image file is the same as the data on the disk.
CRC32 is a CRC technique that uses a 32-bit value to store error checking
information.
When an image file is created, CRC32 details are embedded into the file to ensure
that image file corruption is detected when the image is restored to disk. CRC32
is currently included on a file-by-file basis with FAT partitions and on a volume
basis for NTFS partitions.
In addition to image file error detection, the CRC values are used to verify that
image files and partitions or disks are identical. This offers an additional method
to detect bad sector writes and other drive anomalies that may be missed during
normal imaging checks.
You can generate a text file that contains CRC values and associated file attributes
using the -CRC32 command-line switch.
See “Using the -CRC32 switch” on page 157.
35 Symantec Ghost support for image files and disks
Image files and CRC32