When you are building Windows Server 2012 R2 base images (vSphere Templates) using packer on vSphere (using vmware-iso packer builder); the process usually relies on the windows server to get an IP address automatically via DHCP. This allows the packer builder to then communicate to the server over WinRM and complete the provisioning.

What happens when there is no DHCP available in your vSphere VM Network?

The easy solution is to have the bootstrap of the windows server set a static IP for the server.
This would allow the packer builder to then communicate to the server over WinRM and complete the provisioning.
I already provide an Autounattend.xml to the windows server via the packer floppy_files stanza for the vmware-iso builder.

These user variables are populated with the environment specific floppy files:

I pass the config json file into the packer build command as shown below. This allows us to pass in different config per environment to the same build template for packer.

packer.exe build -var-file=Config-VMWare.json .\PackerBaseWin2012R2-VMWare.json

The Autounattend.xml executes the file a:\vmware-userdata.ps1 as the last step of the FirstLogonCommands setting of the Autounattend process.

The script for this particular environment then uses powershell cmdlets to configure the required static IP address allocated to the Packer Build VM:

Note: If you don’t wait long enough for the boot process to complete; the vmware-iso builder may detect the self assigned IP (169.x.x.x) prior to the userdata script setting the Static IP.
To solve this you can set the vmware-iso builder boot_wait to wait a bit longer, e.g. 10 mins.

This solves how to use packer on vSphere for Windows Server 2012 R2 bootstrapping where you don’t have a DHCP server on the subnet.