Enable IP Address Conflict Detection in DHCP on Windows Server

You may use DHCP server option what detects conflicts by pinging an IP address before offering that address to clients.

DHCP Conflict Detection is useful, if some client use a static ip-address from DHCP pool.

On Windows Server by default DHCP Conflict Detection is disabled.

To enabled DHCP conflict detection

Open DHCP console

On IPv4 settings (or IPv6) select Properties

Go to Advanced tab

Set conflict detection attempts from 1 to 5

To enable DHCP conflict detection from PowerShell

[PS]Set-DhcpServerSetting  -ComputerName <DHCP Server Name> -ConflictDetectionAttempts 1

To view DHCP conflict detection from PowerShell

[PS] Get-DhcpServerSetting -ComputerName <DHCP Server Name>

Note:

Setting conflict detection attempts higher than 2 isn't recommended because each attempt takes as long as 1 second.