Microsoft KB Archive/172912
Article ID: 172912
Article Last Modified on 11/1/2006
- Microsoft Windows NT Server 3.5
- Microsoft Windows NT Server 3.51
- Microsoft Windows NT Server 4.0 Standard Edition
- Microsoft Windows 2000 Server
This article was previously published under Q172912
When you perform Windows mirroring on a computer using IDE drives and the master drive on the primary channel fails, the system may appear to stop responding. You may also experience very erratic mouse movement. This can happen even if the system drive is configured as master on the primary EIDE controller and shadow drive is configured as master on the secondary EIDE controller.
When your computer is running Windows NT or Windows 2000, the ATAPI device driver continues to request communication to the primary EIDE device on the master channel. This process will eventually timeout and Windows will then continue to run by using the primary (shadow) drive on the secondary channel. The length of this timeout delay depends on the processes running and the specific hardware in use.
Because of the nature of IDE architecture, the system may appear to stop responding or erratic mouse movement may occur. This behavior is expected when a mirrored IDE drive fails.
If an instantaneous switchover from the primary drive to the shadow drive of the mirror set is desired, then switching to a SCSI-based disk subsystem is recommended.
When the original system or boot drive fails, you will have to use a Windows NT boot floppy disk to start from the shadow partition or reconfigure the shadow disk drive as the master disk drive on the primary controller.
If the drives are not the same geometry, then you may still not be able to boot off the shadow drive even when moved to the primary drive's position on the IDE channel.
For additional information, please see the following articles with related topics in the Microsoft Knowledge Base:
Keywords: kbhardware KB172912