Script to update the local DNS records based on the DHCP server reservations

Reset-DnsLocalAddresses.ps1

# Reset-DnsLocalAddresses
# Clears and repopulates the automatically managed DNS entries in the server.
#
# Author: Nathan Campos <nathan@innoveworkshop.com>

# Parameters.
[String]$ZoneName = "something.lan"
[IPAddress]$DhcpScope = 192.168.1.0

Function Get-DhcpReservations {
	Get-DhcpServerv4Reservation -ComputerName $env:ComputerName -ScopeId $DhcpScope |
		Select-Object Name,IPAddress |
		Sort-Object -Property { [System.Version]$_.IPAddress }
}

Function Clear-DnsRecords {
	Get-DnsServerResourceRecord -ZoneName $ZoneName -RRType "A" |
		Remove-DnsServerResourceRecord -ZoneName $ZoneName -Force
}

Function Add-DnsReservations {
	Get-DhcpReservations |
		ForEach { New-Object PSObject -Property @{ Name = $_.Name.Split(".")[0].ToLower() -replace "[^a-z0-9-]",""; IPAddress = $_.IPAddress } } |
		ForEach { Add-DnsServerResourceRecordA -Name $_.Name -IPv4Address $_.IPAddress -ZoneName $ZoneName }
}

Clear-DnsRecords
Add-DnsReservations