aznetworktools

0.0.1

Private/VirtualNetwork/CalculateSubnet.ps1


function CalculateSubnet {
    [CmdletBinding()] 
    param (
        [Parameter(Position = 0, Mandatory = $true)][string[]] $Vnets,
        [Parameter(Position = 1, Mandatory = $true)][int] $NumberHostInSubnet,
        [Parameter(Position = 3, Mandatory = $false)][string[]] $ExistedSubnets  
    )
    Process {
        $mask = switch ([int]$NumberHostInSubnet) {
            8 { "29"; break }
            16 { "28"; break }
            32 { "27"; break }
            64 { "26"; break }
            128 { "25"; break }
            256 { "24"; break }
            512 { "23"; break }
            1024 { "22"; break }
        }

        foreach ($vnet in $Vnets) {
            #$vnet='10.2.1.0/24'
            
            $v = IpCalc -Net $vnet
            $totalip = [int]$v.TotalHosts
            $freeip = $totalip - [int]$NumberHostInSubnet
            $lastip = $v.Broadcast
            
            if ($freeip -ge 0) {
                
                $adress = $vnet.Split("/")[0]
                $adress = $adress + "/" + $mask
       
                $checkadressinsubnets = IsIpInSubnets -ExistedSubnets $ExistedSubnets -Min $v.HostMin -Broadcast $v.Broadcast
                
                if (!$checkadressinsubnets) {
                    return $adress
                }
                
                $ip = $null
                $v = IpCalc -Net $ExistedSubnets[0]
                $lastip = $v.Broadcast
                
                while ($true) {   

                
                    if ($ip) {
                        $t = $ip
                    }
                    else {
                        $t = $lastip
                    }
                    
                    $ip = NextIp $t
                    
                    $adress = $ip + "/" + $mask
                
                    $ipcalc = IpCalc $adress
                    $checkadressinsubnets = IsIpInSubnets -ExistedSubnets $ExistedSubnets -Min $ipcalc.HostMin -Broadcast $ipcalc.Broadcast

                        
                    if (!$checkadressinsubnets) {
                        break
                    }
                }
                $checkvnet = IpCalc $vnet -Contains  $ipcalc.Broadcast
                if ($checkvnet) {
                    return $adress
                }
            }
            continue
        }
        return $null
    }
}