Network-FixDns.ps1

#!/usr/bin/env pwsh
# Simple DNS Cleanup Tool
# Fixes broken DNS configurations safely

Write-Host "=== DNS Cleanup Tool ===" -ForegroundColor Cyan
Write-Host "Checking for broken DNS servers..." -ForegroundColor Gray

$brokenDns = @()
$allDns = Get-DnsClientServerAddress -AddressFamily IPv4 | Where-Object { $_.ServerAddresses.Count -gt 0 }

foreach ($dnsConfig in $allDns) {
    $interfaceStatus = (Get-NetAdapter -Name $dnsConfig.InterfaceAlias -ErrorAction SilentlyContinue).Status
    Write-Host "Testing $($dnsConfig.InterfaceAlias) ($interfaceStatus)..." -ForegroundColor Gray
    
    foreach ($server in $dnsConfig.ServerAddresses) {
        Write-Host "  Checking $server..." -NoNewline
        try {
            $null = Resolve-DnsName -Name "google.com" -Server $server -ErrorAction Stop -TimeoutInSeconds 3
            Write-Host " OK" -ForegroundColor Green
        } catch {
            Write-Host " BROKEN" -ForegroundColor Red
            $brokenDns += @{
                Interface = $dnsConfig.InterfaceAlias
                Status = $interfaceStatus
                Server = $server
            }
        }
    }
}

if ($brokenDns.Count -eq 0) {
    Write-Host "`nAll DNS servers are working! No cleanup needed." -ForegroundColor Green
    exit 0
}

Write-Host "`nFound broken DNS servers:" -ForegroundColor Yellow
foreach ($broken in $brokenDns) {
    Write-Host "  $($broken.Server) on $($broken.Interface) ($($broken.Status))" -ForegroundColor Red
}

$fix = Read-Host "`nFix these automatically? (y/N)"
if ($fix -notmatch '^[Yy]') {
    Write-Host "No changes made." -ForegroundColor Gray
    exit 0
}

Write-Host "`nFixing DNS issues..." -ForegroundColor Cyan
foreach ($broken in $brokenDns) {
    Write-Host "Fixing $($broken.Interface)..." -ForegroundColor Yellow
    try {
        if ($broken.Status -eq "Up") {
            Set-DnsClientServerAddress -InterfaceAlias $broken.Interface -ServerAddresses @("8.8.8.8", "8.8.4.4")
            Write-Host "  Set reliable DNS" -ForegroundColor Green
        } else {
            Set-DnsClientServerAddress -InterfaceAlias $broken.Interface -ResetServerAddresses
            Write-Host "  Cleared DNS from disconnected interface" -ForegroundColor Green
        }
    } catch {
        Write-Host "  Failed: $($_.Exception.Message)" -ForegroundColor Red
    }
}

Write-Host "`nDNS cleanup complete!" -ForegroundColor Green
Write-Host "Test with: .\Network-DetailedDiagnostics.ps1" -ForegroundColor Cyan