您必须先删除预订，然后使用首选设置重新添加。

$newip="132.4.5.214"
$query = Get-DhcpServerv4Reservation -ScopeId $scopeid -ComputerName $serverName | WHERE {$_.IPAddress.IPAddressToString-eq $testip}
        if($query.Name){
            $ip = $query.IPAddress.IPAddressToString
            Remove-DhcpServerv4Reservation -ComputerName $serverName -IPAddress $ip
            Add-DhcpServerv4Reservation -ScopeId $scopeid -ComputerName $serverName-IPAddress $newIP -ClientId $query.ClientId -Name $query.Name
}