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ASR Cannot Restore System Disk to Replacement Disk of Identical Size

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This article was previously published under Q314686

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When you attempt to use Automated System Recovery (ASR) to restore to a replacement system or disk, you may receive the following error message, even if the new system disk appears to be the same size as the original system disk:
Setup was unable to restore the configuration of your system
because of the following error:

The capacity of the current system disk drive is
insufficient, and cannot be used to recover the
partitions on the original system disk.

The replacement hard disk drives must be at least as large
as the disks present on the original system.

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This behavior can occur if the replacement disk is slightly smaller than the original system disk, even though they are shown as having the same amount of space. This can occur because two disks that appear to be of the same size may not have the same number of sectors, due to differences in disk geometry and rounding errors in the display of disk space.

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To resolve this behavior, use a replacement disk that has identical disk geometry to the original disk, or use a larger disk.

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This behavior is by design.

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More information

Slight differences in the number of available sectors on a disk may also occur between disks that are the same make and model, but which have different firmware revisions.

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Keywords: KB314686, kbprb

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Article Info
Article ID : 314686
Revision : 6
Created on : 3/2/2007
Published on : 3/2/2007
Exists online : False
Views : 201