Output of Azure subnets with links to attached VNet, route table and NSG

Question

I'm currently working on a script that gives me the output of every Subnet in an Azure Subscription, with links to the VNet, NSG, and the Route Table. The Route Table Name is currently missing in the script, but I want to focus on fixing the NSG right now. This is what my Script looks like:

$VNets = Get-AzVirtualNetwork
$NSG = Get-AzNetworkSecurityGroup
$VNets | ForEach-Object {
    $VNettemp = $_
    $result = $_.Subnets | Select-Object @{Label="Subnet Name";Expression={$_.Name}},@{Label="Subnet";Expression={$_.AddressPrefix}}
    $_ | ForEach-Object {
        $result | Add-Member -Name "VNet Name" -Value $_.Name -MemberType NoteProperty
    }
    if ($_.Subnets.NetworksecurityGroup -ne "null"){
        $NSG | ForEach-Object{
            if ($VNettemp.Subnets.Id -contains $_.Subnets.Id ){
                $result | Add-Member -Name "NSG Name" -Value $_.name -MemberType NoteProperty -Force
            }
        }

    }
return $result
}

The output looks like this:

Subnet Name             Subnet        VNet Name       NSG Name           
-----------             ------        ---------       --------           
default-subnet          10.10.10.0/28 vnet-ine-test   test-nsg           
vnet-ine-test-snet-test 10.10.0.0/24  vnet-ine-test   test-nsg           
default                 10.0.0.0/24   vnet-chn-docker vnet-chn-docker-nsg
vnet-test-subnet        10.0.1.0/24   vnet-chn-docker vnet-chn-docker-nsg

The desired output would look like this because 'default-subnet' and 'vnet-test-subnet' have no NSG attached:

Subnet Name             Subnet        VNet Name       NSG Name
-----------             ------        ---------       --------
default-subnet          10.10.10.0/28 vnet-ine-test           
vnet-ine-test-snet-test 10.10.0.0/24  vnet-ine-test   test-nsg        
default                 10.0.0.0/24   vnet-chn-docker vnet-chn-docker-nsg        
vnet-test-subnet        10.0.1.0/24   vnet-chn-docker

Does anybody know how to fix the output? I tried it with an else statement that fills in an empty value for "NSG Name" but then the name gets canceled entirely for the whole VNet. Thanks for the Help!

Jim Xu Jim Xu · Accepted Answer · 2020-12-24T05:57:14

Regarding the issue, please refer to the following script

$VNets = Get-AzVirtualNetwork
$NSG = Get-AzNetworkSecurityGroup
$resports=@()
$info = @{ "Subnet Name"=""; "Subnet"=""; "VNet Name"="" ; "NSG Name"=""}
foreach($VNet in $VNets){
   $info.'VNet Name'=$VNet.Name
   $info.'NSG Name'=$null
   Foreach($sub in $VNet.Subnets){
     $info.'Subnet Name' =$sub.Name
     $info.Subnet=$sub.AddressPrefix
     if($sub.NetworkSecurityGroup -ne $null){
         $NSG | ForEach-Object{
            if ($VNet.Subnets.Id -contains $_.Subnets.Id ){
                $info.'NSG Name'=$_.Name
            }
        }
     
     }
      $obj=New-Object PSObject -Property $info
      $resports +=$obj

   }

  
}

Output of Azure subnets with links to attached VNet, route table and NSG

1 Answers