Which SCSI Controller to use for Virtual machine?

When we create a virtual machine, we can see the storage controller setting as below.


Lets see what each of them do mean before we talk about changing the controller type for a VM.
Bus Logic ParallelFirst emulated vSCSI controllers available in the VMware platform. In Windows server 2000, this driver available by default. This adapter has queue depth of 1 hence less performance.

LSI Logic Parallel

This is another emulated vSCSI controller available in the VMware platform.  Most operating systems had a driver that supported a queue depth of 32 and it became a very common choice, if not the default.


This is an evolution of the parallel driver to support a new future facing standard.  It began to grown popularity when Microsoft required its use for MCSC within Windows 2008 or newer.

VMware Paravirtual (aka PVSCSI)

This vSCSI controller is virtualization aware and was been designed to support very high throughput with minimal processing cost and is therefore the most efficient driver.

As we have talked about these controllers, let us talk about changing controllers.
When we do create VM, as per our OS selection, VM creation wizard will automatically select the SCSI controller that is best suited for that instance of operating system. Before you make decision to change to any other type of controller, make sure you check that the guest operating system does support that type of controller or else unexpected issues may occur. Reference: VMwale blogDo refer VMWare KB article on how to change the SCSI controller.

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