<i>This answer was submitted by virtualization expert Rick Vanover:</i>
Virtualization's impact is substantial. In some cases, such as VMware's ESX, it effects the server provisioning process because VMware ESX provides the drivers for various HBA's and storage systems. From the switch perspective, it makes obtaining information about the number of paths a little different from what is done on other operating systems. Here are some good resources to check out what administrators are doing in this area:
Troubleshooting SAN configurations:
<a href="http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1282176,00.html ">http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1282176,00.html </a>
Proprietary drivers explained, enlightened:
<a href="http://itknowledgeexchange.techtarget.com/virtualization-pro/proprietary-esx-drivers-explained-enlightened/ ">http://itknowledgeexchange.techtarget.com/virtualization-pro/proprietary-esx-drivers-explained-enlightened/ </a>