I have successfully implemented a Windows Deployment Server in my environment, built both x86 and x64 boot images to support UEFI and Legacy BIOS using the Microsoft Deployment Toolkit (v8450), and have been able to successfully PXE-Boot both a physical machine (HP Z4) and a Virtual Machine (VM version 13 running on ESXi 6.5 host). Additionally, I have created the relevant DHCP Vendor Classes and Policies to ensure the right boot file is being served to the appropriate PXEClient (i.e., UEFI vs BIOS).
That said, when booting using UEFI (with Secure Boot enabled), I have observed two things (the second being of concern, hence my posting this question):
During the boot process, the physical machine successfully contacts the WDS Server and pulls down the boot image in about 6 seconds, then goes on to complete the OS install in about 6 - 8 minutes.
During the boot process, the virtual machine also successfully contacts the WDS Server and pulls down the boot image. However, it takes upwards of 45 minutes to 1 hour to grab the boot image. After that, the OS install completes in about the same time as the physical box (just about 8 minutes).
To troubleshoot, I confirmed that the WDS Server wasn't experiencing any technical issues that would affect its NIC performance. I did check the VM's NIC configuration and found it to be using the E1000E adapter type - so I changed it to use the VMXNET 3 adapter type instead. This made a slight improvement.
So, I decided to do a Wireshark packet capture to see if I could see anything different in the way the physical machine and the VM were communicating with the WDS Server. Well the only thing that stood out to me is the following:
- The Physical Machine used the TFTP protocol
- The Virtual Machine used the UDP protocol
As such, does someone know if there's a setting somewhere that's instructing the Virtual Machine to prefer the UDP protocol over TFTP? I have found nothing definitive in the VMware documentation other than a statement to the fact that PXE-Booting a VM was possible and supported.
Any assistance is definitely appreciated, thanks and my apologies for the lengthy narrative.