Common questions about Defender for Servers

No. When you enable Microsoft Defender for Servers on an Azure subscription, all connected machines are protected by Defender for Servers. Servers that don't have the Log Analytics agent or Azure Monitor agent installed are also protected.

When you enable Defender for Servers on a subscription, you're charged for all machines based on their power states.

Azure VMs:

Azure Arc machines:

When you enable the Servers plan on the subscription level, Defender for Cloud automatically enables the plan on your default workspaces automatically. If you're using a custom workspace, you need to select it to enable the plan. Note that:

• If you turn on Defender for Servers for a subscription and for a connected custom workspace, you aren't charged for both. The system identifies unique VMs.
• If you enable Defender for Servers on cross-subscription workspaces:
  • For the Log Analytics agent, connected machines from all subscriptions are billed, including subscriptions that don't have the Defender for Servers plan enabled.
  • For the Azure Monitor agent, billing and feature coverage for Defender for Servers depends only on the plan being enabled in the subscription.

You can enable Microsoft Defender for Servers at the Log Analytics workspace level, but only servers reporting to that workspace will be protected and billed, and those servers won't receive some benefits, such as vulnerability assessment, and just-in-time VM access.

For every VM that's connected to the workspace, you get 500 MB of free data ingestion per day. The allowance is specifically for the security data types that are directly collected by Defender for Cloud.

This allowance is a daily rate that's averaged across all nodes. Your total daily free limit is equal to [number of machines] × 500 MB. You aren't charged extra if the total doesn't exceed your total daily free limit, even if some machines send 100 MB and others send 800 MB.

Defender for Cloud billing is closely tied to the billing for Log Analytics. Microsoft Defender for Servers provides an allocation of 500 MB per node per day for machines against the following subset of security data types:

• SecurityAlert
• SecurityBaseline
• SecurityBaselineSummary
• SecurityDetection
• SecurityEvent
• WindowsFirewall
• ProtectionStatus
• Update and UpdateSummary when the Update Management solution isn't running in the workspace or solution targeting is enabled.
• MDCFileIntegrityMonitoringEvents

If the workspace is in the legacy per-node pricing tier, the Defender for Cloud and Log Analytics allocations are combined and applied jointly to all billable ingested data.

Yes. You're charged for all machines that are protected by Defender for Servers in Azure subscriptions. The term machines includes Azure virtual machines, instances of Azure Virtual Machine Scale Sets, and Azure Arc-enabled servers. Machines that don't have Log Analytics installed are covered by protections that don't depend on the Log Analytics agent.

The inventory view lists your Defender for Cloud connected resources from a Cloud Security Posture Management (CSPM) perspective. The filters show only the resources with active recommendations.

For example, if you have access to eight subscriptions but only seven currently have recommendations, filter by Resource type = Subscriptions shows only the seven subscriptions with active recommendations:

Not all Defender for Cloud monitored resources requires agents. For example, Defender for Cloud doesn't require agents to monitor Azure Storage accounts or PaaS resources, such as disks, Logic Apps, Data Lake Analysis, and Event Hubs.

When pricing or agent monitoring isn't relevant for a resource, nothing is shown in those columns of inventory.

A Deny all traffic rule is recommended when, as a result of running the algorithm, Defender for Cloud doesn't identify traffic that should be allowed, based on the existing NSG configuration. Therefore, the recommended rule is to deny all traffic to the specified port. The name of this type of rule is displayed as "System Generated". After enforcing this rule, its actual name in the NSG will be a string comprised of the protocol, traffic direction, "DENY", and a random number.

To deploy the Guest Configuration extension with its prerequisites:

• For selected machines, follow the security recommendation Guest Configuration extension should be installed on your machines from the Implement security best practices security control.

• At scale, assign the policy initiative Deploy prerequisites to enable Guest Configuration policies on virtual machines.

The list of resources in the Not applicable tab includes a Reason column. Some of the common reasons include:

Yes. When you enable Microsoft Defender for Servers on an Azure subscription, you'll be charged for all machines that are connected to your Azure subscription. The term machines include Azure virtual machines, Azure Virtual Machine Scale Sets instances, and Azure Arc-enabled servers. Machines that don't have Log Analytics installed are covered by protections that don't depend on the Log Analytics agent.

If a machine, reports to multiple workspaces, and all of them have Defender for Servers enabled, the machines will be billed for each attached workspace.

Yes. If you configure your Log Analytics agent to send data to two or more different Log Analytics workspaces (multi-homing), you'll get 500-MB free data ingestion for each workspace. It's calculated per node, per reported workspace, per day, and available for every workspace that has a 'Security' or 'AntiMalware' solution installed. You'll be charged for any data ingested over the 500-MB limit.

You receive a daily allowance of 500 MB of free data ingestion for each virtual machine (VM) connected to the workspace. This allocation specifically applies to the security data types collected directly by Defender for Cloud.

The data allowance is a daily rate calculated across all connected machines. Your total daily free limit is equal to the [number of machines] x 500 MB. So even if on a given day some machines send 100 MB and others send 800 MB, if the total data from all machines doesn't exceed your daily free limit, you won't be charged extra.

Defender for Cloud's billing is closely tied to the billing for Log Analytics. Microsoft Defender for Servers provides a 500 MB/node/day allocation for machines against the following subset of security data types:

• SecurityAlert
• SecurityBaseline
• SecurityBaselineSummary
• SecurityDetection
• SecurityEvent
• WindowsFirewall
• ProtectionStatus
• Update and UpdateSummary when the Update Management solution isn't running in the workspace or solution targeting is enabled.

If the workspace is in the legacy Per Node pricing tier, the Defender for Cloud and Log Analytics allocations are combined and applied jointly to all billable ingested data. To learn more on how Microsoft Sentinel customers can benefit, please see the Microsoft Sentinel Pricing page.

You can view your data usage in two different ways, the Azure portal, or by running a script.

To view your usage in the Azure portal:

1. Sign in to the Azure portal.

2. Navigate to Log Analytics workspaces.

3. Select your workspace.

4. Select Usage and estimated costs.

   

You can also view estimated costs under different pricing tiers by selecting for each pricing tier.

To view your usage by using a script:

1. Sign in to the Azure portal.

2. Navigate to Log Analytics workspaces > Logs.

3. Select your time range. Learn about time ranges.

4. Copy and past the following query into the Type your query here section.

   let Unit= 'GB';
   Usage
   | where IsBillable == 'TRUE'
   | where DataType in ('SecurityAlert', 'SecurityBaseline', 'SecurityBaselineSummary', 'SecurityDetection', 'SecurityEvent', 'WindowsFirewall', 'MaliciousIPCommunication', 'SysmonEvent', 'ProtectionStatus', 'Update', 'UpdateSummary')
   | project TimeGenerated, DataType, Solution, Quantity, QuantityUnit
   | summarize DataConsumedPerDataType = sum(Quantity)/1024 by  DataType, DataUnit = Unit
   | sort by DataConsumedPerDataType desc
   

5. Select Run.

   

You can learn how to Analyze usage in Log Analytics workspace.

Based on your usage, you won't be billed until you've used your daily allowance. If you're receiving a bill, it's only for the data used after the 500-MB limit is reached, or for other service that doesn't fall under the coverage of Defender for Cloud.

You might want to manage your costs and limit the amount of data collected for a solution by limiting it to a particular set of agents. Use solution targeting to apply a scope to the solution and target a subset of computers in the workspace. If you're using solution targeting, Defender for Cloud lists the workspace as not having a solution.

Next steps

Plan your Defender for Servers deployment