DHCP test client is a great tool to use in DHCP server trouble shooting proces.
This sniffs the network until a DHCP Offer / DHCP Ack is detected on UDP port 68 and shows the received information.
The benefit of the DHCP test client is that you don’t have to install anything, just run the tool and initiate a DHCP request.
Before executing PS Script, script execution has to be enabled in PS:
Get-ExecutionPolicy Set-ExecutionPolicy RemoteSigned
Since the DhcpInterfaceOptions is always accessible (even when the client already received the DHCP offer) you can always read the content. PowerShell script reads the registry key for each DHCP enabled NIC and shows the received DHCP options.
The script shows all Dhcp options and vendor specific Dhcp options (43).
The archive contains three files
DhcpOptions.csv – Semicolon separated file containing all Dhcp Options (IANA) and their data type; DhcpOptionsVS.csv – Semicolon separated file containing some vendor specific Dhcp Options; ReadDhcpOptions.ps1 – The actual PowerShell script
DHCP Options list: