5 no networking in windows vista guests, 6 windows guests may cause a high cpu load – Sun Microsystems VIRTUALBOX VERSION 3.1.0_BETA2 User Manual

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11 Troubleshooting

These problems are all caused by a bug in the hard disk driver of Windows 2000.

After issuing a hard disk request, there is a race condition in the Windows driver code
which leads to corruption if the operation completes too fast, i.e. the hardware in-
terrupt from the IDE controller arrives too soon. With physical hardware, there is a
guaranteed delay in most systems so the problem is usually hidden there (however it
should be possible to reproduce it on physical hardware as well). In a virtual environ-
ment, it is possible for the operation to be done immediately (especially on very fast
systems with multiple CPUs) and the interrupt is signaled sooner than on a physical
system. The solution is to introduce an artificial delay before delivering such inter-
rupts. This delay can be configured for a VM using the following command:

VBoxManage setextradata VMNAME

"VBoxInternal/Devices/piix3ide/0/Config/IRQDelay" 1

This sets the delay to one millisecond. In case this doesn’t help, increase it to a value

between 1 and 5 milliseconds. Please note that this slows down disk performance.
After installation, you should be able to remove the key (or set it to 0).

11.2.4 How to record bluescreen information from Windows

guests

When Windows guests run into a kernel crash, they display the infamous bluescreen.
Depending on how Windows is configured, the information will remain on the screen
until the machine is restarted or it will reboot automatically. During installation, Win-
dows is usually configured to reboot automatically. With automatic reboots, there is
no chance to record the bluescreen information which might be important for problem
determination.

VirtualBox provides a method of halting a guest when it wants to perform a reset.

In order to enable this feature, issue the following command:

VBoxManage setextradata VMNAME "VBoxInternal/PDM/HaltOnReset" 1

11.2.5 No networking in Windows Vista guests

Unfortunately, with Vista, Microsoft dropped support for the virtual AMD PCNet card
that we are providing to virtual machines. As a result, after installation, Vista guests
initially have no networking. VirtualBox therefore ships a driver for that card with the
Windows Guest Additions; see chapter

4.3.5

,

Windows Vista networking

, page

64

.

Starting with version 1.6.0 VirtualBox can emulate an Intel E1000 network device

which is supported by Vista without any third-party drivers.

11.2.6 Windows guests may cause a high CPU load

Several background applications of Windows guests, especially virus scanners, are
known to increases the CPU load notably even if the guest appears to be idle. We
recommend to deactivate virus scanners within virtualized guests if possible.

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