Recovering from Loss of FT Disk Configuration Information

• Microsoft Windows NT Advanced Server version 3.1

SYMPTOMS

You have fault tolerant partitions (such as Stripes with Parity and Mirrors), but cannot access them and they appear in Disk Administrator as type Unknown.

This problem may occur after you have replaced your boot drive and installed Windows NT Advanced Server on it.

RESOLUTION

To avoid experiencing this problem, save the disk configuration whenever there is a change, such as adding fault tolerance. You can do this in Disk Administrator from the Partition menu by choosing Configuration, and then choosing Save. This information can be used to restore the configuration if it is lost by choosing Configuration from the Partition menu, and then choosing Restore.

If the disk configuration was not saved or the information is not available, do the following:

1. Obtain a copy of EDITREG.EXE, and run it on the server (type EDITREG).

   NOTE: EDITREG.EXE can be obtained from Microsoft Product Support.

   WARNING! EDITREG.EXE directly modifies data in the configuration Registry. It is considered unsupported, and should be used only as a last resort. Microsoft cannot guarantee the results of using this tool, and Microsoft cannot guarantee that any problems resulting from the use of EDITREG can be solved. Use this tool at your own risk.

   The following are definitions of EDITREG.EXE commands:

         DISKS: reads the information stored in the Registry key
            HKEY_LOCAL_MACHINE->System->DISK.
   
         MAKEFT: writes into the information stored in the Registry key
            HKEY_LOCAL_MACHINE->System->DISK.
   
   

2. At the prompt, type the following and press ENTER:

         MAKEFT
   

3. Follow the prompts, taking care to conform to the following guidelines:

   a. FT Group Numbers start at 0, so if you have a mirror and a stripe

         set, they will be FT Group 0 and 1
   

   b. Disks are numbered starting at disk 0, exactly as they appear in Disk

         Administrator
   

   c. Partitions are numbered starting at 1

   d. When all components of that set are entered, hit return on the next

         prompt
   

   e. Verify the information by typing DISKS

   f. Quit EDITREG.EXE

4. Shut down and reboot the computer.

5. Open Disk Administrator. Make sure the FT set is type Unknown, but will be color-coded as the correct FT type.

6. Assign a drive letter.

7. Shutdown and reboot

8. From CP Devices select FTDISK, STARTUP is set to Disable, click Startup botton and select "Start Type" as Boot, click OK. With FTDISK selected, click Start.

9. At this point the drive should be usable again.