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---
title: "Quarantine"
description: Quarantine behavior is explained in detail.
ms.author: v-bshilpa
author: v-bshilpa
manager: dansimp
ms.assetid:
ms.reviewer:
ms.prod: w10
ms.mktglfcycl: deploy
ms.sitesec: library
ms.pagetype: security
ms.localizationpriority: normal
audience: ITPro
ms.collection: M365-security-compliance
ms.topic: conceptual
ms.date: 11/17/2020
---
# Quarantine
One of the security challenges that network administrators face is configuring a machine properly after a network change.
Network changes can happen frequently. Additionally, the operations required to re-categorize the network after a change and apply the correct security policies on a machine are non-trivial and may require considerable CPU time. This is especially true for machines that are domain joined. In the past, the delay in applying security policies during network re-categorization has been successfully exploited for vulnerabilities.
To counter this potential exploitation, Windows Firewall will "quarantine" an interface until the system has successfully re-categorized the network and WFP has the correct filters applied for the updated interface configuration. During quarantine, all new inbound connections without exceptions are blocked to the machine.
While the quarantine feature has long been a part of Windows Firewall, the features behavior has often caused confusion for customers unaware of quarantine and its motivations.
Ultimately, the goal of this document is to describe the feature at a high level and help network administrators understand why application traffic is sometimes blocked by quarantine.
## Quarantine Filters
The quarantine feature creates filters which can be split into three categories:
1. Quarantine Default Inbound Block Filter
2. Quarantine Default Exception Filters
3. Interface Un-quarantine Filters
These filters are added in the FWPM_SUBLAYER_MPSSVC_QUARANTINE sublayer and these layers:
1. FWPM_LAYER_ALE_AUTH_CONNECT_V4
2. FWPM_LAYER_ALE_AUTH_CONNECT_V6
3. FWPM_LAYER_ALE_AUTH_RECV_ACCEPT_V4
4. FWPM_LAYER_ALE_AUTH_RECV_ACCEPT_V6
Its important to note that any FW rules customers add will not affect the filters in the quarantine sublayer as filters from FW rules are added in the FWPM_SUBLAYER_MPSSVC_WF sublayer. In other words, customers cannot add their own exception filters to prevent packets from being evaluated by quarantine filters.
For more information about WFP layers and sublayers, see [WFP Operation](https://docs.microsoft.com/en-us/windows/win32/fwp/basic-operation).
### Quarantine Default Inbound Block Filter
The Quarantine Default Inbound Block filter effectively blocks any new non-loopback inbound connections if the packet is not explicitly permitted by another filter in the quarantine sublayer.
### Quarantine Default Exception Filters
When the interface is in quarantine state, the Quarantine Default Exception filters will permit new inbound connections given that they meet the conditions of an exception filter. One example of the exception filters is the Quarantine Default Inbound Loopback Exception filter. This exception filter allows all loopback packets when the interface is in quarantine state.
### Interface Un-quarantine filter
The Interface Un-quarantine filters allows all non-loopback packets if the interface is successfully categorized.
## Quarantine Flow
The following describes the general flow of quarantine:
1. There is some change on the current network interface.
2. The Interface Un-quarantine filters will no longer permit new inbound connections. The interface is now in quarantine state.
3. All non-loopback inbound connections are either permitted by Quarantine Default Exception Filters OR dropped by the Quarantine Default Inbound Block filter.
4. The WFP filters applicable to the old interface state are removed.
5. The WFP filters applicable to the new interface state are added, and the Interface Un-quarantine filters are updated with the current interfaces state.
6. The interface has now exited quarantine state as the Interface Un-quarantine filters permit any new non-loopback packets.
## Quarantine Diagnostics
There are two methods of identifying packet drops from the Quarantine Default Inbound Block Filter.
Given that the network connectivity issue is reproducible, diagnostic traces can be collected by running the following in an administrative command prompt:
```console
Netsh wfp cap start
<Reproduce network connectivity issue>
Netsh wfp cap stop
```
These commands generate a wfpdiag.cab. Inside the .cab exists a wfpdiag.xml, which contains drop netEvents and filters that existed during that repro.
Inside the wfpdiag.xml, search for netEvents which have FWPM_NET_EVENT_TYPE_CLASSIFY_DROP as the netEvent type. To find the relevant drop events, search for the drop events with matching destination IP address, package SID, or application ID name.
The characters in the application ID name will be separated by periods:
```XML
<asString> \\.d.e.v.i.c.e.\\.h.a.r.d.d.i.s.k.v.o.l.u.m.e.1.\\.w.i.n.d.o.w.s.\\.s.y.s.t.e.m.3.2.\\.s.v.c.h.o.s.t...e.x.e... </asString>
```
The netEvent will have more information about the packet that was dropped including information about its capabilities, the filter that dropped the packet, and much more.
If the filter that dropped that packet was by the Quarantine Default Inbound Block filter, then the drop netEvent will have filterOrigin as “Quarantine Default”.
Sample netEventwith filterOrigin “Quarantine Default”
```XML
<netEvent>
<header>
<timeStamp>2020-10-07T01:03:56.281Z</timeStamp>
<flags numItems="9">
<item>FWPM_NET_EVENT_FLAG_IP_PROTOCOL_SET</item>
<item>FWPM_NET_EVENT_FLAG_LOCAL_ADDR_SET</item>
<item>FWPM_NET_EVENT_FLAG_REMOTE_ADDR_SET</item>
<item>FWPM_NET_EVENT_FLAG_LOCAL_PORT_SET</item>
<item>FWPM_NET_EVENT_FLAG_REMOTE_PORT_SET</item>
<item>FWPM_NET_EVENT_FLAG_APP_ID_SET</item>
<item>FWPM_NET_EVENT_FLAG_USER_ID_SET</item>
<item>FWPM_NET_EVENT_FLAG_IP_VERSION_SET</item>
<item>FWPM_NET_EVENT_FLAG_PACKAGE_ID_SET</item>
</flags>
<ipVersion>FWP_IP_VERSION_V4</ipVersion>
<ipProtocol>17</ipProtocol>
<localAddrV4>255.255.255.255</localAddrV4>
<remoteAddrV4>10.195.33.252</remoteAddrV4>
<localPort>21</localPort>
<remotePort>61706</remotePort>
<scopeId>0</scopeId>
<appId>
<data>5c00640065006d00330032005c0073007600630068006f00730074002e006500780065000000</data>
<asString>\.d.e.v.i.c.e.\.h.a.r.d.d.i.s.k.v.o.l.u.m.e.1.\.w.i.n.d.o.w.s.\.s.y.s.t.e.m.3.2.\.s.v.c.h.o.s.t...e.x.e...</asString>
</appId>
<userId>S-1-5-19</userId>
<addressFamily>FWP_AF_INET</addressFamily>
<packageSid>S-1-0-0</packageSid>
<enterpriseId/>
<policyFlags>0</policyFlags>
<effectiveName/>
</header>
<type>FWPM_NET_EVENT_TYPE_CLASSIFY_DROP</type>
<classifyDrop>
<filterId>66241</filterId>
<layerId>44</layerId>
<reauthReason>0</reauthReason>
<originalProfile>0</originalProfile>
<currentProfile>0</currentProfile>
<msFwpDirection>MS_FWP_DIRECTION_OUT</msFwpDirection>
<isLoopback>false</isLoopback>
<vSwitchId/>
<vSwitchSourcePort>0</vSwitchSourcePort>
<vSwitchDestinationPort>0</vSwitchDestinationPort>
</classifyDrop>
<internalFields>
<internalFlags numItems="1">
<item>FWPM_NET_EVENT_INTERNAL_FLAG_FILTER_ORIGIN_SET</item>
</internalFlags>
<capabilities/>
<fqbnVersion>0</fqbnVersion>
<fqbnName/>
<terminatingFiltersInfo numItems="3">
<item>
<filterId>66241</filterId>
<subLayer>FWPP_SUBLAYER_INTERNAL_FIREWALL_QUARANTINE</subLayer>
<actionType>FWP_ACTION_BLOCK</actionType>
</item>
<item>
<filterId>74045</filterId>
<subLayer>FWPP_SUBLAYER_INTERNAL_FIREWALL_WSH</subLayer>
<actionType>FWP_ACTION_BLOCK</actionType>
</item>
<item>
<filterId>73602</filterId>
<subLayer>FWPP_SUBLAYER_INTERNAL_FIREWALL_WF</subLayer>
<actionType>FWP_ACTION_BLOCK</actionType>
</item>
</terminatingFiltersInfo>
<filterOrigin>Quarantine Default</filterOrigin>
<interfaceIndex>5</interfaceIndex>
</internalFields>
</netEvent>
```
Alternatively, If the Filtering Platform Connection failure auditing is enabled, the drop event will be logged in Windows Event Viewer:
To enable Filtering Platform Connection audits, run the following command in an administrative command prompt
```console
Auditpol /set /category:"System" /SubCategory:"Filtering Platform Connection" /success:enable /failure:enable
```
Sample Drop Audit with Filter Origin “Quarantine Default”
[image]
Once the drops filter origin has been identified as the Quarantine Default Inbound Block filter, the interface should be further investigated. To find the relevant interface, use the interface index value from the netEvent or event audit in the following PowerShell command to generate more information about the interface:
```Powershell
Get-NetIPInterface InterfaceIndex <Interface Index>
Get-NetIPInterface InterfaceIndex 5
```
[image]
Using the interface name, Event Viewer can be searched for any interface related changes.
To enable more networking audit events, see [Enable IPsec and Windows Firewall Audit Events](https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/cc754714(v=ws.10)?redirectedfrom=MSDN).
Packet drops from the Quarantine Default Inbound Block filter are often transient and do not signify anything more than a network change on the interface.