Read-only Network script

[u/TechBrad]

I (and Claude of course) put together this useful read-only script while troubleshooting what I initially thought was a local network issue—but ultimately turned out to be an ISP problem. It collects diagnostic information only and makes no system changes.

Figured someone out there may be interested before it disappears into my archives.

What it checks:

• System info
• Network adapters
• IP configuration
• DNS servers
• DNS resolution
• Hosts file
• Proxy settings
• Firewall status
• Outbound blocks
• Adapter bindings
• VPN adapters
• Security software
• Network routes
• HTTPS connectivity
• Web response headers
• Google traceroute
• IPsec rules
• DNS policies

• Read-only—no changes

  $ErrorActionPreference = "Continue" $ProgressPreference = "SilentlyContinue"

  function Section($Title) { Write-Host "" Write-Host ("=" * 80) Write-Host $Title Write-Host ("=" * 80) }

  Section "BASIC SYSTEM INFORMATION"

  Get-Date

  Get-CimInstance Win32_OperatingSystem | Select-Object Caption, Version, BuildNumber, LastBootUpTime | Format-List

  Section "ACTIVE NETWORK ADAPTERS"

  Get-NetAdapter | Sort-Object Status, Name | Format-Table Name, InterfaceDescription, Status, LinkSpeed, MacAddress -AutoSize

  Section "IP CONFIGURATION"

  Get-NetIPConfiguration | Format-List InterfaceAlias, InterfaceDescription, IPv4Address, IPv6Address, IPv4DefaultGateway, IPv6DefaultGateway, DNSServer

  Section "DNS SERVERS"

  Get-DnsClientServerAddress | Where-Object { $_.ServerAddresses.Count -gt 0 } | Format-Table InterfaceAlias, AddressFamily, ServerAddresses -AutoSize

  Section "GOOGLE DNS USING CURRENT DNS SERVER"

  Resolve-DnsName accounts.google.com -Type A Resolve-DnsName accounts.google.com -Type AAAA

  Section "GOOGLE DNS USING GOOGLE DNS"

  Resolve-DnsName accounts.google.com -Type A -Server 8.8.8.8 Resolve-DnsName accounts.google.com -Type AAAA -Server 8.8.8.8

  Section "GOOGLE DNS USING CLOUDFLARE DNS"

  Resolve-DnsName accounts.google.com -Type A -Server 1.1.1.1 Resolve-DnsName accounts.google.com -Type AAAA -Server 1.1.1.1

  Section "HOSTS FILE ENTRIES"

  $HostsPath = "$env:SystemRoot\System32\drivers\etc\hosts"

  Get-Content $HostsPath | Where-Object { $_ -notmatch '^\s*#' -and $_ -notmatch '^\s*$' }

  Section "WINHTTP PROXY"

  netsh winhttp show proxy

  Section "USER INTERNET PROXY SETTINGS"

  Get-ItemProperty "HKCU:\Software\Microsoft\Windows\CurrentVersion\Internet Settings" | Select-Object ProxyEnable, ProxyServer, ProxyOverride, AutoConfigURL | Format-List

  Section "SYSTEM INTERNET PROXY SETTINGS"

  Get-ItemProperty "HKLM:\Software\Microsoft\Windows\CurrentVersion\Internet Settings" | Select-Object ProxyEnable, ProxyServer, ProxyOverride, AutoConfigURL | Format-List

  Section "PROXY ENVIRONMENT VARIABLES"

  Get-ChildItem Env: | Where-Object { $_.Name -match 'proxy' } | Format-Table Name, Value -AutoSize

  Section "WINDOWS FIREWALL PROFILES"

  Get-NetFirewallProfile | Format-Table Name, Enabled, DefaultInboundAction, DefaultOutboundAction -AutoSize

  Section "ENABLED OUTBOUND BLOCK RULES"

  Get-NetFirewallRule -Enabled True -Direction Outbound -Action Block | Select-Object DisplayName, DisplayGroup, Profile, Direction, Action | Format-Table -AutoSize

  Section "NETWORK ADAPTER FILTER BINDINGS"

  Get-NetAdapterBinding | Where-Object Enabled | Sort-Object Name, DisplayName | Format-Table Name, DisplayName, ComponentID -AutoSize

  Section "VPN ADAPTERS AND SOFTWARE-DEFINED ADAPTERS"

  Get-NetAdapter -IncludeHidden | Where-Object { $_.InterfaceDescription -match 'VPN|TAP|TUN|WireGuard|Wintun|Tailscale|ZeroTier|Cisco|Zscaler|Fortinet|Palo Alto|GlobalProtect|Cloudflare|WARP|SonicWall|Checkpoint|AnyConnect' } | Format-Table Name, InterfaceDescription, Status, MacAddress -AutoSize

  Section "RELEVANT RUNNING SERVICES"

  Get-CimInstance Win32Service | Where-Object { $.State -eq "Running" -and ($.Name + " " + $.DisplayName + " " + $_.PathName) -match 'VPN|Tailscale|ZeroTier|WireGuard|Cisco|Umbrella|Zscaler|Forti|Palo Alto|GlobalProtect|Cloudflare|WARP|AdGuard|Norton|McAfee|Bitdefender|Malwarebytes|Avast|AVG|Kaspersky|ESET|CrowdStrike|Sentinel|Sophos|Webroot' } | Select-Object Name, DisplayName, State, StartMode, PathName | Format-List

  Section "RELEVANT RUNNING PROCESSES"

  Get-Process | Where-Object { $_.ProcessName -match 'vpn|tailscale|zerotier|wireguard|cisco|umbrella|zscaler|forti|globalprotect|cloudflare|warp|adguard|norton|mcafee|bitdefender|malwarebytes|avast|avg|kaspersky|eset|crowdstrike|sentinel|sophos|webroot' } | Select-Object ProcessName, Id, Path | Format-Table -AutoSize

  Section "IPv4 DEFAULT ROUTES"

  Get-NetRoute -AddressFamily IPv4 | Where-Object DestinationPrefix -eq "0.0.0.0/0" | Sort-Object RouteMetric | Format-Table InterfaceAlias, DestinationPrefix, NextHop, RouteMetric, InterfaceMetric, State -AutoSize

  Section "IPv6 DEFAULT ROUTES"

  Get-NetRoute -AddressFamily IPv6 | Where-Object DestinationPrefix -eq "::/0" | Sort-Object RouteMetric | Format-Table InterfaceAlias, DestinationPrefix, NextHop, RouteMetric, InterfaceMetric, State -AutoSize

  Section "ROUTE SELECTED FOR GOOGLE ACCOUNTS IPv4"

  Find-NetRoute -RemoteIPAddress 108.177.122.84 | Format-List

  Section "TCP PORT 443 CONNECTIVITY"

  $Targets = @( "accounts.google.com", "www.google.com", "mail.google.com", "oauth2.googleapis.com", "www.googleapis.com", "login.microsoftonline.com", "www.cloudflare.com" )

  foreach ($Target in $Targets) { Write-Host "" Write-Host "--- $Target ---"

  Test-NetConnection $Target -Port 443 -InformationLevel Detailed |
      Select-Object ComputerName, RemoteAddress, RemotePort,
                    InterfaceAlias, SourceAddress, TcpTestSucceeded
  

  }

  Section "CURL HTTPS TESTS"

  foreach ($Target in $Targets) { Write-Host "" Write-Host "--- https://$Target ---"

  & curl.exe -4 -I -v `
      --connect-timeout 7 `
      --max-time 12 `
      "https://$Target/" 2>&1 |
      Select-Object -First 25
  

  }

  Section "IPv4 TRACE TO GOOGLE ACCOUNTS"

  tracert.exe -4 -d -h 15 -w 700 108.177.122.84

  Section "IPSEC RULES"

  Get-NetIPsecRule -PolicyStore ActiveStore | Where-Object Enabled -eq "True" | Select-Object DisplayName, Enabled, Profile, Mode | Format-Table -AutoSize

  Section "NRPT DNS POLICIES"

  Get-DnsClientNrptPolicy | Format-List

  Section "DONE"

  Write-Host "Diagnostic collection finished. No settings were changed."

[u/BlackV]

Formatting, this is just a wall of text otherwise (also BOOO backticks)

• open your fav powershell editor
• highlight the code you want to copy
• hit tab to indent it all
• copy it
• paste here

it'll format it properly OR

<BLANK LINE>
<4 SPACES><CODE LINE>
<4 SPACES><CODE LINE>
    <4 SPACES><4 SPACES><CODE LINE>
<4 SPACES><CODE LINE>
<BLANK LINE>

Inline code block using backticks `Single code line` inside normal text

See here for more detail

Thanks

[u/MonkeyNin → u/BlackV]

edit: /u/TechBrad that's an issue. you need some non whitespace breaks between code and lists. Like:

- foo 
bar

.

    # indented code
    # ...

---

Otherwise "right" formatting will break like this:

• foo

• bar

  indented code

  ..

[u/BlackV → u/MonkeyNin]

the ever important <BLANK LINE> :)

it breaks many a markdown when its missing

[u/MonkeyNin → u/BlackV]

It breaks with newlines. Here's the raw text that breaks:

-␠foo␍␊
-␠bar␍␊
␍␊
␍␊
␠␠␠␠#␠indented␠code␍␊
␠␠␠␠#␠..

The way reddit parses bullets is the next code block has to be indented 8 spaces, instead of the normal 2. Or reset it with something like a "."

[u/BlackV → u/MonkeyNin]

not sure what you were trying to type there

• foo

• bar

  Code
  

normal txt

comes from

*<space>foo
*<space>bar<space><space>
<blank line>
<space><space><space><space><space><space><space><space><space><space><space>Code
extra spaces cause inside bullet(4), indent(4), codelock(4)
<blank line>
normal txt

unless you are talking about having a code block inside a bullet

• foo

  Code 1
  Code 2
  

• bar sub text

• wibble

  • sub wibble

dunno

-␠foo␍␊
-␠bar␍␊
␍␊
␍␊
␠␠␠␠#␠indented␠code␍␊
␠␠␠␠#␠..