.NET agent configuration

This document contains the configuration options for the New Relic APM .NET agent. Both the .NET Framework agent and the .NET Core agent use the same configuration options and have the same APM features, unless otherwise stated.

Configuration overview

New Relic APM agent configuration options allow you to control some aspects of how the agent behaves. Some of these config options are part of the basic install process (like setting your license key and app name), but most are more advanced settings, such as: setting a log level, setting up proxy host access, excluding certain attributes, and enabling distributed tracing.

The .NET agent gets its configuration from the newrelic.config file, which is generated as part of the install process. By default, only a global newrelic.config file is created, but you can also create app-local newrelic.config files for finer control over a multi-app system. Other ways to set config options include: using environment variables, or setting server-side configuration from the UI. For more on the various config options and what overrides what, see Config settings precedence.

Both .NET agents (.NET Framework and .NET Core) use the same configuration options and have the same APM features, unless otherwise stated.

If you make changes to the config file and want to validate that it's in the right format, you can check it against the XSD file (located at C:\ProgramData\New Relic\.NET Agent\newrelic.xsd) with any XSD validator.

For IIS: after you change your newrelic.config or app.config file, perform an IISRESET from an administrative command prompt. Log level adjustments do not require a reset.

Configuration settings precedence

By default, the .NET agent only includes a global configuration file named newrelic.config. The agent provides additional configuration options, all of which override the global newrelic.config settings.

.NET configuration precedence
Environment variables are the highest precedence (for .NET Framework these will usually be set automatically as part of most install processes; for .NET Core, you must set them during the install process). Then, settings in your web.config or app.config override app-local newrelic.config files. App-local newrelic.config files and some server-side configuration settings override the global newrelic.config file.
.NET configuration Levels of precedence
Environment variables

Takes highest precedence. For more about these, see Required environment variables.
App-local newrelic.config

You can create app-local newrelic.config files to configure individual apps on a multi-app system. These local configuration files override the settings in the global newrelic.config file.

The agent looks for app-local config files in the following directories, in this order:

  • A directory specified in your web.config or app.config file with the NewRelic.ConfigFile property
  • The web app's root directory (with the app.config or web.config)
  • The directory containing your app's executable file
Server-side configuration

You can also configure some settings using server-side configuration. For some settings, server-side configuration overrides the local setting. For others, the local setting overrides the server-side configuration.
Default (global) newrelic.config

The .NET profiler reads this to determine what applications to profile (this can be overridden with local app.config or web.config). App-specific settings are still determined using the precedence described in this table.

Any settings entered in your local web.config or app.config will override the equivalent settings in the global newrelic.configfile. If a local newrelic.config file exists, it will be used in place of a global newrelic.config file. The global file's location depends on your .NET agent.

  • .NET Core agent: Always located in your installation directory.
  • .NET Framework agent: Located in the New Relic agent home directory, %ALLUSERSPROFILE%\New Relic\.NET Agent. (Exception: For Windows 2003, it is in %ALLUSERSPROFILE%\Application Data\New Relic\.NET Agent.)

Required environment variables

New Relic's .NET Framework and .NET Core agents rely on environment variables to tell the .NET Common Language Runtime (CLR) to attach New Relic to your processes. Some .NET agent install procedures (like the MSI installer) will automatically set these variables for you; some procedures will require you to manually set them.

.NET Framework environment variables

For the .NET Framework agent, the following variables are required:

COR_ENABLE_PROFILING=1
COR_PROFILER={71DA0A04-7777-4EC6-9643-7D28B46A8A41}
NEWRELIC_INSTALL_PATH=path\to\agent\directory

The .NET Framework MSI installer will add these to IIS or as system-wide environment variables.

.NET Core environment variables

For the .NET Core agent, the following variables are required:

Linux:

CORECLR_ENABLE_PROFILING=1
CORECLR_PROFILER={36032161-FFC0-4B61-B559-F6C5D41BAE5A}
CORECLR_NEWRELIC_HOME=path/to/agent/directory
CORECLR_PROFILER_PATH="${CORECLR_NEWRELIC_HOME}/libNewRelicProfiler.so"

Windows:

CORECLR_ENABLE_PROFILING=1
CORECLR_PROFILER={36032161-FFC0-4B61-B559-F6C5D41BAE5A}
CORECLR_NEWRELIC_HOME=path\to\agent\directory
CORECLR_PROFILER_PATH=path\to\agent\directory\NewRelic.Profiler.dll

If your system has previously used monitoring services (non-New Relic), you may have a "profiler conflict" when trying to install and use the New Relic agent. More details:

Profiler conflict explanation

New Relic’s .NET agents rely on environment variables to tell the .NET Common Language Runtime (CLR) to load New Relic into your processes. The install-related environment variables are Microsoft variables, not New Relic variables. They can be used by other .NET profilers, and only one profiler can be attached to a process at a time. For this reason, if you have used previous application monitoring products, you may have profiler conflicts.

For specific install instructions, see the .NET agent install documentation.

Setup options

Use these options to setup and configure your agent. The New Relic .NET agent supports the following categories of setup options:

The root element of the configuration document is a configuration element.

<configuration xmlns="urn:newrelic-config"
  agentEnabled="true"
  maxStackTraceLines="50"
  timingPrecision="low">

The configuration element supports the following attributes:

agentEnabled
Type Boolean
Default true

Enable or disable the New Relic agent.

maxStackTraceLines
Type Integer
Default 80

The maximum number of stack frames to trace in any stack dump.

timingPrecision
Type String
Default low

Controls the precision of the timers. High precision will provide better data, but at a lower execution speed. Possible values are high and low.

The first child of the configuration element is a service element. The service element configures the agent's connection to the New Relic service.

<service licenseKey="YOUR_LICENSE_KEY"
  sendEnvironmentInfo="true"
  syncStartup="false"
  sendDataOnExit="false"
  sendDataOnExitThreshold="60000"
  autoStart="true"/>

The service element supports the following attributes:

licenseKey (REQUIRED)
Type String
Default (none)

Your New Relic license key. New Relic uses the license key to match your app's data to the correct account in the UI.

sendEnvironmentInfo
Type Boolean
Default true

Instructs the agent to record execution environment information. Environment information includes operating system, agent version, and which assemblies are available.

syncStartup
Type Boolean
Default false

Block application startup until the agent connects to New Relic. If set to true, the first transaction may take substantially longer to complete, because it is blocked until the connection to New Relic is finished.

sendDataOnExit
Type Boolean
Default false

Block application shutdown until the agent sends all data from the latest harvest cycle.

sendDataOnExitThreshold
Type Integer
Default 60000
Unit Milliseconds

The minimum amount of time the process must run before the agent blocks it from shutting down. This setting only applies when sendDataOnExit is true.

requestTimeout
Type Integer
Default

2000 (sendDataOnExit enabled)

120000 (sendDataOnExit disabled)
Unit Milliseconds

The agent's request timeout when communicating with New Relic.

autoStart
Type Boolean
Default

True

Automatically start the .NET agent when the first instrumented method is hit.

ssl (DEPRECATED)
Type Boolean
Default

true

The option to disable SSL is valid only for .NET agent versions 7.x and earlier. .NET agent version 8.x and higher communicate only via SSL.

The agent communicates with New Relic via HTTPS by default, and New Relic requires HTTPS for all traffic to New Relic APM and the New Relic REST API.

The proxy element is an optional child of the service element. Use the proxy element if you want the agent to communicate with New Relic service via a proxy.

<proxy
  host="hostname"
  port="PROXY_PORT"
  uriPath="path/to/something.aspx"
  domain="mydomain.com"
  user="PROXY_USERNAME"
  password="PROXY_PASSWORD"/>

The proxy element supports the following attributes:

host
Type String
Default (none)

Defines the proxy host.

port
Type Integer
Default 8080

Defines the proxy port.

uriPath
Type String
Default (none)

Optionally define a proxy URI path.

domain
Type String
Default (none)

Optionally define a domain to use when authenticating with the proxy server.

user
Type String
Default (none)

Optionally define a user name for authentication.

password
Type String
Default (none)

Optionally define a password for authentication.

The log element is a child of the configuration element. The log element configures New Relic's logging . The agent generates its own log file to keep its logging information separate from your application's logs.

<log level="info"
  auditLog="false"
  console="false"
  directory="PATH\TO\LOG\DIRECTORY"
  fileName="FILENAME.log" />

The log element supports the following attributes:

level
Type String
Default info

Defines the level of detail recorded in the log file. Possible values, in increasing order of detail, are:

  • off
  • error
  • warn
  • info
  • debug
  • finest
  • all

Increasing the logging level will increase New Relic's performance impact.

auditLog
Type Boolean
Default false

Records all data sent to and received from New Relic in both an auditlog log file and the standard log file.

console
Type Boolean
Default false

Send log messages to the console, in addition to the log file.

directory
Type String
Default C:\ProgramData\New Relic\.NET Agent\Logs

The directory to hold log files generated by the agent. If this is omitted, then a directory named logs in the New Relic Agent installation area will be used by default.

fileName
Type String
Default (none)

Defines a name for the log file. If you do not define a fileName, the name is derived from the name of the monitored process.

The application element is a child of the configuration element. This element defines your application name, and disables or enables sampling. This element is required.

name
Type String
Default My Application

The name of your .NET application is a child of the application element. New Relic will aggregate your data according to this name. For example, if you have two running applications named AppA and AppB, you will see two applications in the New Relic interface: AppA and AppB.

You can also assign up to three names to your app. The first name is the primary name. For example:

<application>
  <name>MY APPLICATION PRIMARY</name>
  <name>SECOND APP NAME</name>
  <name>THIRD APP NAME</name> 
</application>
disableSamplers
Type Boolean
Default false

Samplers collect information about memory and CPU consumption. Set this to true to disable sampling.

The dataTransmission element is a child of the configuration element. This element affects how data is sent to New Relic and can be used if you have specific data transmission requirements.

<dataTransmission
  putForDataSend="false"
  compressedContentEncoding="deflate"/>

The dataTransmission element supports the following attributes:

putForDataSend
Type Boolean
Default false

Defines the HTTP method used when sending data to New Relic. Set this to true to enable using the PUT method when sending data. The POST method is used by default.

If the default host name label in the APM UI is not useful, you can decorate that name in the New Relic UI with a display name. After the application process is restarted and the .NET agent is reporting again, the display name will show in the servers list (as seen in the example below), in addition to the default host name.

To set a display name, choose one of the following options. The environment variable takes precedence over the config file value.

Set via config file

Set displayName attribute in the processHost ​element in newrelic.config. The processHost element is a child of the configuration element.

<configuration . . . >
   <processHost displayName="CUSTOM_NAME" />
</configuration>
Set via environment variable

Set the NEW_RELIC_PROCESS_HOST_DISPLAY_NAME environment variable:

NEW_RELIC_PROCESS_HOST_DISPLAY_NAME = "CUSTOM_NAME"

Restart your application to see your changes in the New Relic UI.

crop-cosmetic-label-hostname.png

Instrumentation options

Use these options to configure which elements of your application and environment to instrument. New Relic for .NET supports the following categories of instrumentation options:

The instrumentation element is a child of the configuration element. By default, the .NET agent instruments IIS asp worker processes and Azure web and worker roles. To instrument other processes, see Instrumenting custom applications.

The applications element is a child of the instrumentation element. The applications element specifies which non-web apps to instrument. It contains a name attribute.

This is not the same as the application (configuration) element, which is a child of the configuration element.

<instrumentation>
  <applications>
    <application name="MyService1.exe" />
    <application name="MyService2.exe" />
    <application name="MyService3.exe" />
  </applications>
</instrumentation>

An attribute is a key/value pair that determines the properties of an event or transaction. Each attribute is sent to APM transaction traces, APM error traces, Insights Transaction events, Insights TransactionError events, or Insights PageView events. The primary attributes element enables or disables attribute collection for the .NET agent, and defines specific attributes to collect or exclude. You can also configure attribute settings based on their destination: Error collection, transaction traces, Browser instrumentation, and transaction events.

In this example, the agent excludes all attributes whose key begins with myApiKey (myApiKey.bar, myApiKey.value), but collects the custom attribute myApiKey.foo.

<attributes enabled="true"> 
  <exclude>myApiKey.*</exclude>
  <include>myApiKey.foo</include>
</attributes>

You can view the .NET APM attributes on the .NET agent attributes page. You can also define custom attributes with the agent API call AddCustomParameter.

enabled
Type Boolean
Default true

Enable or disable attribute collection. When set to false in the primary attribute element, this setting overrides all attribute settings for individual destinations.

include
Type String
Default (none)

If attributes are enabled, the agent will collect all attribute keys specified in this list. To specify multiple attribute keys, specify each individually. You can also use a * wildcard character at the end of a key to match multiple attributes (for example, myApiKey.*). For more information, see Attribute rules.

exclude
Type String
Default (none)

If attributes are enabled, the agent will not collect attribute keys specified in this list. To specify multiple attribute keys, specify each individually. You can also use a * wildcard character at the end of a key to match multiple attributes (for example, myApiKey.*). For more information, see Attribute rules.

Feature options

Use these options to enable, disable, and configure New Relic features. New Relic for .NET allows you to configure the following features:

This is only applicable to a system's global config file.

The applicationPools element is a child of the configuration element. The applicationPools element specifies for the profiler exactly which application pools to instrument and uses the same name as the IIS application pool name. This configuration element is useful when you may need to instrument only a small subset of your app pools. For example, a given server might have several hundred application pools, but only a few of those pools need to be instrumented by the .NET agent.

Here is an example of disabling instrumentation for specific application pools:

<applicationPools>
  <applicationPool name="Foo" instrument="false"/>
  <applicationPool name="Bar" instrument="false"/>
</applicationPools>

Here is an example of disabling instrumentation for all application pools currently executing on the server and enabling instrumentation for specific application pools:

<applicationPools>
  <defaultBehavior instrument="false"/>
  <applicationPool name="Foo" instrument="true"/>
  <applicationPool name="Bar" instrument="true"/>
</applicationPools>

The applicationPools element supports the following elements:

defaultBehavior
Type Boolean
Default false

Defines how the .NET agent will behave on a "global" level for application pools served via IIS. The .NET agent instruments all application pools by default. When true, application pools listed under applicationPool with an instrument attribute set to false will not be instrumented.

Essentially, when set to false, the application pool list act as a whitelist. When set to true, the application pool list acts as a blacklist.

applicationPool

Defines instrumentation behavior for a specific application pool. The name attribute is the name of an application pool. Enable or disable profiling in the instrument attribute. Define this application in the name attribute.

A distributed tracing feature is now available. Distributed tracing improves on cross application tracing; it's recommended for monitoring activity in complex distributed systems.

Not supported for self-hosted WCF applications.

The crossApplicationTracer element is a child of the configuration element. crossApplicationTracer links transaction traces across applications. When linked in a service-oriented architecture, all instrumented applications that communicate with each other via HTTP will now "link" transaction traces with the applications that they call and the applications they are called by. Cross application tracing makes it easier to understand the performance relationship between services and applications.

<crossApplicationTracer enabled="true"/>

The crossApplicationTracer element supports the following attribute:

enabled
Type Boolean
Default true

Enable or disable cross application tracing

The errorCollector element is a child of the configuration element. errorCollector configures error collection, which captures information about uncaught exceptions and sends them to New Relic.

<errorCollector enabled="true" captureEvents="true" maxEventSamplesStored="100">
  <ignoreErrors>
    <exception>System.IO.FileNotFoundException</exception>
    <exception>System.Threading.ThreadAbortException</exception>
  </ignoreErrors>
  <ignoreStatusCodes>
    <code>401</code>
    <code>404</code>
  </ignoreStatusCodes>
  <attributes enabled="true">
    <exclude>myApiKey.*</exclude>
    <include>myApiKey.foo</include>
  </attributes>
</errorCollector>

For an overview of error configuration in New Relic APM, see Manage errors in APM.

The errorCollector element supports the following elements and attributes:

enabled
Type Boolean
Default true

Enable or disable the error collector.

captureEvents
Type Boolean
Default true

Enable or disable the capturing of error events.

maxEventSamplesStored
Type Integer
Default 100

Reservoir limit for error events.

ignoreErrors
Type String
Default (none)

Lists specific exceptions to not report to New Relic. The full name of the exception should be used, such as System.IO.FileNotFoundException.

ignoreStatusCodes
Type String
Default (none)

Lists specific HTTP error codes to not report to New Relic. You can use standard integral HTTP error codes, such as just 401, or you may use Microsoft full status codes with decimal points, such as 401.4 or 403.18.

attributes

Use this sub-element to customize your agent attribute settings for error traces. This sub-element uses the same settings as the primary attributes element: enabled, include, and exclude.

The highSecurity element is a child of the configuration element. To enable high security mode, set this property to true and enable high security property in the New Relic user interface. Enabling high security means SSL is turned on, request parameters and custom parameters are not collected, strip exception messages is enabled, and queries cannot be sent to New Relic in their raw form.

enabled
Type Boolean
Default false

Enable or disable high security mode. Example:

<highSecurity enabled="true"/>

The stripExceptionMessages element is a child of the configuration element. To enable strip exception messages, set this property to true. By default, this is set to false, which means that the agent sends messages from all exceptions to the New Relic collector. If you enable high security mode, this is automatically changed to true, and the agent strips the messages from exceptions.

enabled
Type Boolean
Default false

Enable or disable strip exception messages. Example:

<stripExceptionMessages enabled="true"/>

The transactionEvents element is a child of the configuration element. Use transactionEvents to configure transaction events.

<transactionEvents enabled="true"
  maximumSamplesStored="10000">
 <attributes enabled="true">
    <exclude>myApiKey.*</exclude>
    <include>myApiKey.foo</include>
  </attributes>
</transactionEvents>

The transactionEvents element supports the following attributes:

enabled
Type Boolean
Default true

Enable or disable the event recorder.

maximumSamplesStored
Type Integer
Default 10000

The maximum number of samples to store in memory at once.

attributes

Use this sub-element to customize your agent attribute settings for transaction events. This sub-element uses the same settings as the primary attributes element: enabled, include, and exclude.

The customEvents element is a child of the configuration element. Use customEvents to configure custom events.

<customEvents enabled="true" maximumSamplesStored="10000"/>

The CustomEvents element supports the following attributes:

enabled
Type Boolean
Default true

Enable or disable the event recorder.

maximumSamplesStored
Type Integer
Default 10000

The maximum number of samples to store in memory at once.

The customParameters element is a child of the configuration element. Use customParameters to configure custom parameters.

<customParameters enabled="true" />

The CustomParameters element supports the following attributes:

enabled
Type Boolean
Default true

Enable or disable the capture of custom parameters.

Labels

The labels element is a child of the configuration element. This sets the label names and values to associate with the application. The list is a semicolon delimited list of colon-separated name and value pairs. You can also use with the NEW_RELIC_LABELS environment variable. Example:

<labels>foo:bar;zip:zap</labels>

The browserMonitoring element is a child of the configuration element. browserMonitoring configures New Relic Browser in your .NET application. Browser gives you insight your end users' performance experience. This is accomplished by measuring the time it takes for your users' browsers to download and render your webpages by injecting a small amount of JavaScript code into the header and footer of each page.

// If you use both the Exclude and Attribute elements
// the Exclude element must be listed first.
<browserMonitoring autoInstrument="true">
  <requestPathsExcluded>
    <path regex="url-regex-1"/>
    <path regex="url-regex-2"/>
    ...
    <path regex="url-regex-n"/>
  </requestPathsExcluded>
  <attributes enabled="true">
    <exclude>myApiKey.*</exclude>
    <include>myApiKey.foo</include>
  </attributes>
</browserMonitoring>

The browserMonitoring element supports the following attributes:

autoInstrument
Type Boolean
Default true

By default the agent automatically injects the Browser agent JavaScript. To turn off automatic injection, set this attribute to false.

attributes

Use this sub-element to customize your agent attribute settings for Browser. This sub-element uses the same settings as the primary attributes element: enabled, include, and exclude.

requestPathsExcluded

Use this sub-element to prevent the Browser agent from being injected in specific pages. The element is used as follows:

<requestPathsExcluded>
  <path regex="url-regex-1"/>
  <path regex="url-regex-2"/>
  ...
  <path regex="url-regex-n"/>
</requestPathsExcluded>

The agent will not inject the Browser agent into pages whose URL matches one of the specified regular expressions. The regular expression should follow Microsoft guidelines for the Regex class.

It is a reference to the virtual directory of the path in your application and not the full URL of the path you wish to exclude. For example, to exclude the pages in https://www.mywebsite.com/mywebpages/ you would simply insert /mywebpages/ as the path regex value.

The requestPathsExcluded element should be used in cases where it is impossible or undesirable to use the DisableBrowserMonitoring() call. To minimize a possible performance impact try to use as few regular expressions as possible and keep them as simple as possible.

The slowSql element is a child of the configuration element. slowSql configures capturing information about slow query executions, and captures and obfuscates explain plans for these queries.

<slowSql enabled="true"/>

The slowSql element supports the following attribute:

enabled
Type Boolean
Default true

Enable or disable slow query tracing.

The transactionTracer element is a child of the configuration element. transactionTracer configures transaction traces. Included in the trace is the exact call sequence of the transactions, including any query statements issued.

<transactionTracer enabled="true"
    transactionThreshold="apdex_f"
    stackTraceThreshold="500"
    recordSql="obfuscated"
    explainEnabled="true"
    explainThreshold="500"
    maxSegments="3000"
    maxStackTrace="30"
    maxExplainPlans="20">
  <attributes enabled="true">
    <exclude>myApiKey.*</exclude>
    <include>myApiKey.foo</include>
  </attributes>
 </transactionTracer>

The transactionTracer element supports the following attributes:

enabled
Type Boolean
Default true

Enable or disable transaction traces.

transactionThreshold
Type String
Default apdex_f

Defines the threshold for transaction traces. If a transaction takes longer than the threshold, it is eligible for being traced. See transaction trace basics for more about the rules governing traces.

The default value is apdex_f, which sets the threshold to four times the application's apdex_t value. For more information about apdex_t, see Apdex.

You can also set the threshold to be a specific time value in milliseconds.

recordSql
Type String
Default obfuscated

Select a query tracing policy. Options are off, which records nothing; obfuscated, which records an obfuscated version of the query; or raw, which records the query exactly as it is issued to the database.

Recording raw queries may capture sensitive information.

stackTraceThreshold
Type Integer
Default 500
Unit Milliseconds

Defines the stack trace threshold: this is the threshold at which segments will be given a stack trace in the transaction trace.

explainEnabled
Type Boolean
Default false

When true, the agent captures EXPLAIN statements for slow queries.

explainThreshold
Type Integer
Default 500
Unit Milliseconds

The agent collects slow query data for queries that exceed this threshold, along with any available explain plans, as part of transaction traces.

maxSegments
Type Integer
Default 3000

The maximum number of segments to collect in a transaction trace.

maxStackTrace
Type Integer
Default 30

The maximum number of stack traces to collect during a harvest cycle.

maxExplainPlans
Type Integer
Default 20

The maximum number of explain plans to collect during a harvest cycle.

attributes

Use this sub-element to customize your agent attribute settings for transaction traces. This sub-element uses the same settings as the primary attributes element: enabled, include, and exclude.

The datastoreTracer element is a child of the configuration element.

<datastoreTracer> 
  <instanceReporting enabled="true"  />
  <databaseNameReporting enabled="true" />
  <queryParameters enabled="false" />
</datastoreTracer>

The datastoreTracer element supports the following sub-elements:

instanceReporting

Use this sub-element to enable collection of datastore instance metrics (such as the host and port) for some database drivers. These are reported on slow query traces and transaction traces. The default value of attribute enabled is true.

databaseNameReporting

Use this sub-element to enable collection of the database name on slow query traces and transaction traces for some database drivers. The default value of attribute enabled is true.

queryParameters

Use this sub-element to enable collection of the SQL query parameters on slow query traces. The default value of attribute enabled is false.

  • Recording query parameters may capture sensitive information.
  • The transactionTracer.recordSql configuration option must be set to raw or this option is ignored.

Enabling distributed tracing disables cross application tracing, and has other effects on New Relic APM features. Before enabling, read the transition guide.

Requires .NET agent version 8.6.45.0 or higher.

Not supported for self-hosted WCF applications.

Distributed tracing lets you see the path that a request takes as it travels through a distributed system.

To enable distributed tracing, choose one of the following options:

Enable via config file

Set the <distributedTracing> element to true to enable via the newrelic.config file. This element is a child of the <configuration> element.

<configuration . . . >
   <distributedTracing enabled="true" />
</configuration>
Enable via environment variable

Set the NEW_RELIC_DISTRIBUTED_TRACING_ENABLED environment variable in the application's environment.

NEW_RELIC_DISTRIBUTED_TRACING_ENABLED=true

Settings in app.config or web.config

You can also configure the following settings in your app's app.config or web.config, within the outermost element, <configuration>:

Enable and disable the agent
<appSettings>
   <add key = "NewRelic.AgentEnabled" value="false" />
</appSettings>

This setting does not work with ASP.NET Core apps when using the web.config file.

Application name

For more information, see Name your .NET application.

<appSettings>
   <add key = "NewRelic.AppName" value ="Descriptive Name" />
</appSettings>
License key
<appSettings>
   <add key = "NewRelic.LicenseKey" value ="XXXXXXXX" />
</appSettings>
Change newrelic.config location

Designates an alternative location for the config file outside of the local root of the app or global config location. The location entered must be an absolute path.

<appSettings>
   <add key = "NewRelic.ConfigFile" value="C:\Path-to-alternate-config-dir\newrelic.config" />
</appSettings>

For more help

Recommendations for learning more: