CheckAndAddCnames.ps1

CheckAndAddCnames.ps1

param(
    [Parameter(Mandatory = $false)]
    [string[]]$CnameList,

    [Parameter(Mandatory = $false)]
    [string]$CnameListFilePath,

    [Parameter(Mandatory = $true)]
    [string]$TargetHostname,

    [Parameter(Mandatory = $true)]
    [string]$DnsServer,

    [Parameter(Mandatory = $true)]
    [string]$LookupZone
)

function CheckAndAddCname($cname, $target, $dnsServer, $zone) {
    try {
        $dnsRecord = Resolve-DnsName -Name $cname -Type CNAME -Server $dnsServer -ErrorAction SilentlyContinue
        if ($dnsRecord -and $dnsRecord.QueryType -eq 'CNAME') {
            Write-Host "CNAME $cname already exists, pointing to $($dnsRecord.NameHost). Skipping..."
        } else {
            Write-Host "Creating CNAME $cname pointing to $target..."
            Add-DnsServerResourceRecordCName -HostNameAlias $target -Name $cname -ZoneName $zone -ComputerName $dnsServer
            Write-Host "CNAME $cname created successfully."
        }
    } catch {
        Write-Error "Error processing CNAME $cname : $_"
    }
}

# Determine how to read CNAME list based on parameters provided
if (-not [string]::IsNullOrEmpty($CnameListFilePath)) {
    if (Test-Path -Path $CnameListFilePath) {
        $CnameList = Get-Content -Path $CnameListFilePath
    } else {
        Write-Error "The specified file at $CnameListFilePath does not exist."
        return
    }
}

if ($CnameList -eq $null -or $CnameList.Count -eq 0) {
    Write-Error "No CNAMEs provided to process."
    return
}

foreach ($cname in $CnameList) {
    if (![string]::IsNullOrWhiteSpace($cname)) {
        CheckAndAddCname -cname $cname -target $TargetHostname -dnsServer $DnsServer -zone $LookupZone
    }
}