What Should I Do If a Blue Screen or Service Exception Occurs After a QingTian ECS Running Windows Is Changed to a KVM ECS?

Symptom

When a QingTian ECS running Windows is changed to a KVM ECS, there may be a blue screen of death (BSOD) of startup failure, with the Windows Boot Manager showing an error status code of 0xc000000f.

Possible Causes

ECSs with different architectures load different protocols and different drivers.

• KVM Windows ECSs load the virtio-blk driver, and the corresponding registry is Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\viostor.
• Certain C6 series Windows ECSs load the virtio-scsi driver, and the corresponding registry is Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\vioscsi.

Check whether there is the StartOverride item in the registry path of the driver.

• If the value of the REG_DWORD field is 0, the ECSs use the driver in this path upon the next startup.
• If the value of the REG_DWORD field is not 0, the ECSs do not use the driver in this path upon the next startup.

When a QingTian Windows ECS is changed to a KVM ECS, if the driver of the corresponding protocol used by the system disk is not loaded, the system disk cannot be identified and the ECS cannot be started.

Solution

Rolling back to the original specifications

Before troubleshooting, you can roll back the target ECS to its original specifications by referring to Modifying Specifications of Individual ECSs.

Troubleshooting

After a KVM Windows ECS is rolled back to a QingTian ECS, if you want to change the QingTian ECS to a KVM ECS again, to prevent startup exceptions, do as follows:

1. Make preparations.
   1. Log in to the ECS.
   2. In the Run dialog box, enter regedit to access the registry editor.
   3. In the registry, locate the following entries:

      Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\vioscsi

      Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\viostor

      Check whether the StartOverride item exists.

      • If StartOverride does not exist and there are only Enum and Parameters in the directory, no changes need to be made.
      • If StartOverride exists in the vioscsi directory, go to step 1.d.
      • If StartOverride exists in the viostor directory, go to step 1.e.
   4. Check the StartOverride item in the vioscsi directory. Change the value of the field whose type is REG_DWORD from 0 to 3. (If the value is already 3, you do not need to change it.)
   5. Check the StartOverride item in the viostor directory. Change the value of the field whose type is REG_DWORD from 3 to 0. (If the value is already 0, you do not need to change it.)
   6. Restart the ECS.
   7. Repeat steps 1.b to 1.c to check whether StartOverride exists in the registry.

      If there are only Enum and Parameters in the path, the modification is successful.

2. Modify specifications.

   Change the Windows ECS specifications to the target specifications.