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Improved RPC port wording
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ADDS/README.md

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@@ -40,6 +40,7 @@ Script files referenced by this document are versioned independently:
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|---------------------------------|---------------:|
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| `Set-ADDSFirewallPolicy.ps1` | 2.9 |
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| `CustomRules.Sample.ps1` | 2.8 |
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| `CustomRules.Semperis.ps1` | 1.0 |
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| `RpcNamedPipesFilters.txt` | 2.1 |
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| `Show-WindowsFirewallLog.ps1` | 1.2 |
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| `Undo-ADDSFirewallPolicy.bat` | 2.9 |
@@ -681,12 +682,22 @@ Here is a mnemotechnical example of a static RPC port configuration:
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| DFSR | 5722/TCP |
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| WMI | 24158/TCP |
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These sorts of changes should be thoroughly planned
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and the transition from dynamic ports to static ones should always be coordinated with the networking team
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to prevent any Active Directory (AD) outages.
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Microsoft's Directory Services support team emphasizes this point clearly:
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> [!WARNING]
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> Don't restrict AD/Netlogon to static ports without exhaustively discussing the risks involved,
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> and heavily documenting it.
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References:
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- [How to restrict Active Directory RPC traffic to a specific port](https://learn.microsoft.com/en-us/troubleshoot/windows-server/active-directory/restrict-ad-rpc-traffic-to-specific-port)
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- [Configuring DFSR to a Static Port - The rest of the story](https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/configuring-dfsr-to-a-static-port-the-rest-of-the-story/ba-p/396746)
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- [Setting Up a Fixed Port for WMI](https://learn.microsoft.com/en-us/windows/win32/wmisdk/setting-up-a-fixed-port-for-wmi)
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- [RPC Load Balancing Best Practices](https://learn.microsoft.com/en-us/windows/win32/rpc/load-balancing-best-practices)
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- [Stop Worrying and Love the Outage, Vol II: DCs, custom ports, and Firewalls/ACLs](https://techcommunity.microsoft.com/blog/askds/stop-worrying-and-love-the-outage-vol-ii-dcs-custom-ports-and-firewallsacls/4062773)
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### RPC Dynamic Port Allocation
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@@ -698,12 +709,11 @@ However, this approach does not seem to provide any security benefits.
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Restricting the RPC port range does not prevent any hacking techniques or mitigate any security vulnerabilities,
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nor does it simplify the configuration of network firewalls. Furthermore, going too far can lead to port exhaustion.
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We have therefore decided against including this setting in the `DCFWTool`.
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This is in accordance with the [recommendation](https://techcommunity.microsoft.com/blog/askds/stop-worrying-and-love-the-outage-vol-ii-dcs-custom-ports-and-firewallsacls/4062773)
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from Microsoft's Directory Services support team:
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Microsoft recommends:
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- Don’t restrict AD/Netlogon to static ports without exhaustively discussing the risks involved.
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- Don’t restrict the RPC dynamic range without exhaustively discussing the risks involved.
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Source: [Stop Worrying and Love the Outage, Vol II: DCs, custom ports, and Firewalls/ACLs](https://techcommunity.microsoft.com/blog/askds/stop-worrying-and-love-the-outage-vol-ii-dcs-custom-ports-and-firewallsacls/4062773)
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> [!WARNING]
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> Don't restrict the RPC dynamic range without exhaustively discussing the risks involved, and heavily documenting it.
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### RPC Filters
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