P2V multi processor servers to single processor VMs
One of the major disadvantages of VMware Converter is that you do not have the option to choose how many virtual cpus (vCPU) your new VM will have. If your source physical server has 2 CPU sockets your target VM will end up with 2 vCPUs. If your source server’s CPUs are dual core your target VM ends up with 4 vCPUs. It’s a well known best practice to minimize the number of multi processor VMs in your virtual infrastructure. So, how do you make sure servers that you p2v result in single processor VMs?
It’s a good idea to start by choosing to not power on the VM when the conversion is complete. This gives you the opportunity to reduce the vCPUs before you start the VM’s HAL for the first time, and allows you to remove hardware like COM and parallel ports.
Should you still experience performance issues you will have to modify the VM’s HAL manually.
VMware Communities: How to P2V multi-proc box to uni-proc ..
is forum thread that explains the process of adjusting a multi porcessor HAL carried over during a p2v conversion. I have cleaned up the cut and pasted steps:
Changing the HAL from Multi processor to Single processor after P2V conversion:
- Before making any changes to the VM, Create a Snapshot in Virtual Center.
- RDP or Console into the Server and go to Device Manager
- For Windows Server 2003, install the following hotfix. It does not require a reboot. This hotfix allows you to downgrade to Uniprocessor. WindowsServer2003-KB923425-v2-x86-ENU.exe
- Expand the Computer tab to see what HAL is loaded
- Right click on ACPI Multiprocessor PC and choose Properties
- Click the Driver tab
- Click Update Driver
- Click Next
- Choose Display driver [in order to] choose and click Next
- Choose ?Show all hardware of this device class?
- Choose ACPI Uniprocessor PC and click Next
- You will be warned about changing this driver, but Click Yes to continue
- Click Next
- Click Finish
- Click Close
- You will be asked to reboot the computer.
- If the Computer reboots cleanly and everything seems to work, clean up the Snapshot you took.
- Verify in Device Manager that the HAL has changed.
on February 25th, 2008 at 9:17 pm
[…] http://vmetc.com/2008/02/21/p2v-multi-proc-servers-to-uni-proc-vms/ […]
on June 11th, 2008 at 6:21 am
[…] I also wrote (and sent the customer) a post earlier this year that offers similar advice, but P2V multi processor servers to single processor VMs instructs you to install a patch specifically for Windows Server 2003 VMs which then allows you to […]
on June 11th, 2008 at 6:21 am
[…] I also wrote (and sent the customer) a post earlier this year that offers similar advice, but P2V multi processor servers to single processor VMs instructs you to install a patch specifically for Windows Server 2003 VMs which then allows you to […]