CODEWITHSUNDEEP
powershelldns
unclemeat
unclemeat

Reputation: 5197

Generate list of all DNS records in specified subnet

I need to generate a list of all DNS records for a specified subnet. Is there a way to do this using either the powershell DNS cmdlets, DNSCMD, or anything else, that isn't the very slow way that I am currently using?

I'm enumerating the host names in 17.(7,8,9).162.(16-238).

$HostList = @()

ForEach ($a in 7..9) { 
    ForEach ($b in 16..238) {
        $DNSCheck = Resolve-DNSName "17.$a.162.$b"
        $HostList += ($DNSCheck.NameHost)
    }
}

Write-Host $HostList

What I've ended up using - Many thanks to Ansgar.

$ZoneName = "some.domain"
$DNSHost = "dnsserver"

$Hosts = Get-DnsServerResourceRecord $ZoneName -ComputerName $DNSHost -RRType 'A' |? { 
    $Address = $_.RecordData.IPV4Address.ToString()
    $LastOctet = $Address.Split(".")[-1]
    $Address -like "17.[7-9].162.*" -and $LastOctet -in 16..238
}

ForEach ($H in $Hosts) {
    Write-Host $H.HostName
}

Upvotes: 2

Views: 13066

Answers (3)

Brad Tostenson
Brad Tostenson

Reputation: 15

Here is the best way I found

$Zone = YourDomain.local
Get-DnsServerResourceRecord -ZoneName $Zone -RRType A | Where-Object {$_.RecordData.ipv4address -like "192.168.39.*"}

Upvotes: 0

SystemAdmin
SystemAdmin

Reputation: 21

Use this GridView and filter for your IP-Addresses

$server = "Your_DNS_Server"
$record = Get-WmiObject -Namespace "root\MicrosoftDNS" -ComputerName $server -Class MicrosoftDNS_AType
$record | Select DomainName,RecordData,OwnerName | Sort-Object -Property {[System.Version]$_.RecordData} | Out-GridView

Sorting IP-Addresses is done by [System.Version]

[system.version]("17.7.162.238")
Major  Minor  Build  Revision
-----  -----  -----  --------
17     7      162     238

Upvotes: -1

Ansgar Wiechers
Ansgar Wiechers

Reputation: 200273

Using PowerShell DNS cmdlets and borrowing code from this answer you could do something like this:

$zone  = 'example.com'
$range = '17.7.162.16', '17.7.162.238'

function Addr2UInt($addr) {
  $bytes = $addr.GetAddressBytes()
  [array]::Reverse($bytes)
  [BitConverter]::ToUInt32($bytes, 0)
}

$addrFrom = Addr2UInt ([Net.IPAddress]::Parse($range[0]))
$addrTo   = Addr2UInt ([Net.IPAddress]::Parse($range[1]))

Get-DNSServerResourceRecord $zone -RRType 'A' | ? {
  $addr = Addr2UInt $_.RecordData.IPv4Address;
  $addrFrom -le $addr -and $addr -le $addrTo
}

IPAddress objects can't be compared using operators like -le, but since IP(v4) addresses are basically 32-bit numbers you can convert the bytes of an address to a number for comparison:

$bytes = $addr.GetAddressBytes()
(($bytes[0] * 256 + $bytes[1]) * 256 + $bytes[2]) * 256 + $bytes[3]

The ToUInt32() method provides a more elegant way to do this conversion (makes it more obvious what's happening, too), but since the method expects the Least Significant Byte at the lowest index the array must be reversed first.

The function just wraps the conversion code for convenience, because I need it at 3 places in the script.

Upvotes: 2

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