Microsoft Defender for Identity health issues

Article
02/11/2024

The Microsoft Defender for Identity Health Issues page lists any current health issues for your Defender for Identity deployment and sensors, alerting you to any problems in your Defender for Identity deployment.

Health issues page

The Microsoft Defender for Identity Health issues page lets you know when there's a problem with your Defender for Identity workspace, by raising a health issue. To access the page, follow these steps:

In Microsoft Defender XDR, under Identities, select Health issues.
The Health issues page appears, where you can see health issues for both your general Defender for Identity environment and specific sensors.

Defender for Identity supports the following types of health alerts:
- Domain-related or aggregated health issues, listed on the Global health issues tab
- Sensor-specific health issues, listed on the Sensor health issues tab
Filter issues by status, issue name, or severity to help you find the issue you're looking for.

For example:
Select any issue for more details and the option to close or suppress the issue. For example:

Health issues

This section describes all the health issues for each component, listing the cause and the steps needed to resolve the problem.

Sensor-specific health issues are displayed in the Sensor health issues tab and domain related or aggregated health issues are displayed in the Global health issues tab as detailed in the following tables:

A domain controller is unreachable by a sensor

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor has limited functionality due to connectivity issues to the configured domain controller.	This affects Defender for Identity's ability to detect suspicious activities related to domain controllers monitored by this Defender for Identity sensor.	Make sure the domain controllers are up and running and that this Defender for Identity sensor can open LDAP connections to them. In addition, in Settings make sure to configure a Directory Service account for every deployed forest.	Medium	Sensors health issues tab

All/Some of the capture network adapters on a sensor are not available

Alert	Description	Resolution	Severity	Displayed in
All/Some of the selected capture network adapters on the Defender for Identity sensor are disabled or disconnected.	Network traffic for some/all of the domain controllers is no longer captured by the Defender for Identity sensor. This issue affects the ability to detect suspicious activities, related to those domain controllers.	Make sure these selected capture network adapters on the Defender for Identity sensor are enabled and connected.	Medium	Sensors health issues tab

Directory services user credentials are incorrect

Alert	Description	Resolution	Severity	Displayed in
The credentials for the directory services user account are incorrect.	This issue affects sensors' ability to detect activities using LDAP queries against domain controllers.	- For a standard AD accounts: Verify that the username, password, and domain in the Directory services configuration page are correct. - For group Managed Service Accounts: Verify that the username and domain in the Directory Services configuration page are correct. Also check all the other gMSA account prerequisites described on the Directory Service account recommendations page.	Medium	Global health issues tab

Low success rate of active name resolution

Alert	Description	Resolution	Severity	Displayed in
The listed Defender for Identity sensors are failing to resolve IP addresses to device names more than 90% of the time using the following methods: - NTLM over RPC - NetBIOS - Reverse DNS	This affects Defender for Identity's detections capabilities and might increase the number of false positive alarms.	- For NTLM over RPC: Check that port 135 is open for inbound communication from Defender for Identity sensors on all computers in the environment. - For reverse DNS: Check that the sensors can reach the DNS server and that Reverse Lookup Zones are enabled. - For NetBIOS: Check that port 137 is open for inbound communication from Defender for Identity sensors on all computers in the environment. Additionally, make sure that the network configuration (such as firewalls) isn't preventing communication to the relevant ports.	Low	Sensors health issues tab and Global health issues tab

No traffic received from domain controller

Alert	Description	Resolution	Severity	Displayed in
No traffic was received from the domain controller via this Defender for Identity sensor.	This issue might indicate that port mirroring from the domain controllers to the Defender for Identity sensor isn't configured yet or not working.	Verify that port mirroring is configured properly on your network devices. On the Defender for Identity sensor capture NIC, disable these features in Advanced Settings: Receive Segment Coalescing (IPv4) Receive Segment Coalescing (IPv6)	Medium	Sensors health issues tab and Global health issues tab

Read-only user password to expire shortly

Alert	Description	Resolution	Severity	Displayed in
The read-only user password, used to perform resolution of entities against Active Directory, is about to expire in less than 30 days.	If the password for this user expires, all the Defender for Identity sensors stop running and no new data is collected.	Change the domain connectivity password and then update the Directory Service account password.	Medium	Global health issues tab

Read-only user password expired

Alert	Description	Resolution	Severity	Displayed in
The read-only user password, used to get directory data, expired.	All the Defender for Identity sensors stop running, or will stop running soon, and no new data is collected.	Change the domain connectivity password and then update the Directory Service account password.	High	Global health issues tab

Sensor outdated

Alert	Description	Resolution	Severity	Displayed in
A Defender for Identity sensor is outdated.	A Defender for Identity sensor is running a version that can't communicate with the Defender for Identity cloud infrastructure.	Manually update the sensor and check to see why the sensor isn't automatically updating. If this option doesn't work, download the latest sensor installation package and uninstall and reinstall the sensor. For more information, see Download the Microsoft Defender for Identity sensor and Install the Microsoft Defender for Identity sensor.	Medium	Sensors health issues tab and Global health issues tab

Sensor reached a memory resource limit

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor stopped itself and restarts automatically to protect the domain controller from a low memory condition.	The Defender for Identity sensor enforces memory limitations upon itself to prevent the domain controller from experiencing resource limitations. This issue occurs when memory usage on the domain controller is high. Data from this domain controller is only partly monitored.	Increase the amount of memory (RAM) on the domain controller or add more domain controllers in this site to better distribute the load of this domain controller.	Medium	Sensors health issues tab

Sensor service failed to start

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor service failed to start for at least 30 minutes.	This issue can affect the ability to detect suspicious activities originating from domain controllers that are monitored by this Defender for Identity sensor.	Monitor Defender for Identity sensor logs to understand the root cause for Defender for Identity sensor service failure.	High	Sensors health issues tab

Sensor stopped communicating

Alert	Description	Resolution	Severity	Displayed in
There has been no communication from the Defender for Identity sensor. The default time span for this alert is 5 minutes.	Network traffic is no longer captured by the network adapter on the Defender for Identity sensor. This affects Defender for Identity's ability to detect suspicious activities, since network traffic isn't able to reach the Defender for Identity cloud service.	Check that the port used for the communication between the Defender for Identity sensor and Defender for Identity cloud service isn't blocked by any routers or firewalls.	Medium	Sensors health issues tab

Some Windows events are not being analyzed

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is receiving more events than it can process.	Some Windows events aren't being analyzed. This can affect the ability to detect suspicious activities originating from domain controllers being monitored by this Defender for Identity sensor.	Consider adding more processors and memory as required. If you're using a standalone Defender for Identity sensor, verify that only the required events are forwarded to the sensor. Or, try forwarding some events to another Defender for Identity sensor.	Medium	Sensors health issues tab and Global health issues tab

Some network traffic could not be analyzed

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is receiving more network traffic than it can process.	Some network traffic couldn't be analyzed. This issue can affect the ability to detect suspicious activities originating from domain controllers being monitored by this Defender for Identity sensor.	Consider adding more processors and memory as required. If you're using a standalone Defender for Identity sensor, reduce the number of domain controllers being monitored. This issue can also happen if you're using domain controllers on VMware virtual machines. To avoid these issues, you can check that the following settings are set to 0 or Disabled in the virtual machine (in the Windows OS, not in the VMware settings): - Large Send Offload V2 (IPv4) - IPv4 TSO Offload The names can vary depending on your VMware version. For more information, see your VMware documentation.	Medium	Sensors health issues tab and Global health issues tab

Some ETW events are not being analyzed

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is receiving more Event Tracing for Windows (ETW) events than it can process.	Some Event Tracing for Windows (ETW) events aren't being analyzed. This can affect the ability to detect suspicious activities originating from domain controllers being monitored by this Defender for Identity sensor.	Consider adding more processors and memory as required.	Medium	Sensors health issues tab and Global health issues tab

Sensor running on an operating system that will soon become unsupported

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is running on an operating system that will soon become unsupported.	Windows Server 2012 and 2012 R2 reached end of support on October 10, 2023. More details can be fount at: https://aka.ms/mdi/oseos	The operating system on the server should be upgraded to the latest supported operating system. For more details, see: https://aka.ms/mdi/os	Medium	Sensors health issues tab

Sensor running on an unsupported operating system

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is running on an unsupported operating system.	Windows Server 2012 and 2012 R2 reached end of support on October 10, 2023. More details can be found at: https://aka.ms/mdi/oseos	The operating system on the server should be upgraded to the latest supported operating system. For more details, see: https://aka.ms/mdi/os	High	Sensors health issues tab

Sensor has issues with packet capturing component

Alert	Description	Resolution	Severity	Displayed in
The Defender for Identity sensor is using WinPcap drivers instead of Npcap drivers.	All customers should be using Npcap drivers instead of the WinPcap drivers. Starting with Defender for Identity version 2.184, the installation package installs Npcap 1.0 OEM.	Install Npcap according to the guidance as described in: https://aka.ms/mdi/npcap	Low	Sensors health issues tab
The Defender for Identity sensor is running an Npcap version older than the minimum required version.	The minimum Npcap version supported is 1.0. Starting with Defender for Identity version 2.184, the installation package installs Npcap 1.0 OEM.	Upgrade Npcap according to the guidance as described in: https://aka.ms/mdi/npcap	Medium	Sensors health issues tab
The Defender for Identity sensor is running an Npcap component that is not configured as required.	The Npcap installation is missing the required configuration options.	Install Npcap according to the guidance as described in: https://aka.ms/mdi/npcap	High	Sensors health issues tab

NTLM Auditing is not enabled

Alert	Description	Resolution	Severity	Displayed in
NTLM Auditing isn't enabled.	NTLM Auditing (for event ID 8004) is not enabled on the server. (This configuration is validated once a week, per sensor).	Enable NTLM Auditing events according to the guidance as described at the Event ID 8004 section, in the Configure Windows Event collection page.	Medium	Sensors health issues tab

Directory Services Advanced Auditing is not enabled as required

Alert	Description	Resolution	Severity	Displayed in
Directory Services Advanced Auditing is not enabled as required. (This configuration is validated once a day, per domain).	The Directory Services Advanced Auditing configuration doesn't include all the categories and subcategories as required.	Enable the Directory Services Advanced Auditing events. For more information, see Configure audit policies for Windows event logs.	Medium	Global health issues tab

Directory Services Object Auditing is not enabled as required

Alert	Description	Resolution	Severity	Displayed in
Directory Services Object Auditing is not enabled as required. (This configuration is validated once a day, per domain).	The Directory Services Object Auditing configuration doesn't include all the object types and permissions as required.	Enable the Directory Services Object Auditing events according to the guidance as described in the Configure domain object auditing section, in the Configure Windows Event collection page.	Medium	Global health issues tab

Auditing on the Configuration container is not enabled as required

Alert	Description	Resolution	Severity	Displayed in
Auditing on the Configuration container isn't enabled as required. (This configuration is validated once a day, per domain).	The Directory Services Auditing on the Domain's Configuration container is not enabled as required.	Enable the Directory Services Auditing on the Domain's Configuration container according to the guidance as described in the Configure Audit Policies section, in the Configure Windows Event collection page.	Medium	Global health issues tab

Auditing on the ADFS container is not enabled as required

Alert	Description	Resolution	Severity	Displayed in
Auditing on the ADFS container is not enabled as required. (This configuration is validated once a day, per domain).	The Directory Services Auditing on the ADFS container isn't enabled as required.	Enable the Directory Services Auditing on the ADFS container according to the guidance as described in the Configure auditing on an Active Directory Federation Services (AD FS) section, in the Configure Windows Event collection page.	Medium	Global health issues tab

Power mode is not configured for optimal processor performance

Alert	Description	Resolution	Severity	Displayed in
Power mode is not configured for optimal processor performance. (This configuration is validated once a day, per sensor).	The operating system's power mode isn't configured to the optimal processor performance settings. This issue can affect the server's performance and the sensors' ability to detect suspicious activities.	Do one of the following: - Configure the power option of the machine running the Defender for Identity sensor to High Performance - Set both the minimum and maximum processor state to 100 For more information, see the Sensor requirements and recommendations section in the Defender for Identity prerequisites page.	Low	Sensors health issues tab

Sensor failed to write to the custom log path

Alert	Description	Resolution	Severity	Displayed in
Sensor failed to write to the custom log path.	The custom log path provided in the sensor configuration can't be created.	1. Stop the `AATPSensorUpdater` and `AATPSensor` services. 2. Change the `SensorCustomLogLocation` in the sensor configuration file to a valid path or set it to null. 3. Start the `AATPSensorUpdater` and `AATPSensor` services again.	Low	Sensors health issues tab

Radius accounting (VPN integration) data ingestion failures

Alert	Description	Resolution	Severity	Displayed in
Radius accounting (VPN integration) data ingestion failures.	The listed Defender for Identity sensors have radius accounting (VPN integration) data ingestion failures.	Validate that the shared secret in the Defender for Identity configuration settings matches your VPN server, according to the guidance described Configure VPN in Defender for Identity section, in the Defender for Identity VPN integration page.	Low	Health issues page