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misc:dhcp_test

Checking DHCP Options with DHCP test client

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.

32 bit DHCP test client & 64 bit DHCP client can be downloaded from:

http://files.thecybershadow.net/dhcptest/

Checking DHCP Options with PowerShell script

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).

ReadDhcpOptions

You can find the PowerShell script here: ReadDhcpOptions
or download it from the author's site http://www.ingmarverheij.com/download/5839/

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:

http://www.iana.org/assignments/bootp-dhcp-parameters/bootp-dhcp-parameters.xhtml

misc/dhcp_test.txt · Last modified: 2016/02/10 07:36 (external edit)