Use the OpenTelemetry.DotNet.Auto.psm1
PowerShell module
to set up automatic instrumentation for IIS:
# Import the module
Import-Module "OpenTelemetry.DotNet.Auto.psm1"
# Install core files
Install-OpenTelemetryCore
# Setup IIS instrumentation
Register-OpenTelemetryForIIS
Warning
Register-OpenTelemetryForIIS
performs IIS restart.
Note This is NOT required for ASP.NET Core deployments.
This step is necessary only for ASP.NET (.NET Framework).
Note There are three distinct options.
Add OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule
by modifying and extending web.config
(first two options)
or applicationHost.config
(third option).
<system.web>
<httpModules>
<add name="TelemetryHttpModule" type="OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule" />
</httpModules>
</system.web>
Warning After applying above changes you might experience following error as this configuration requires IIS classic mode. In order to fix it you can switch to classic mode or use other options.
.
<system.webServer>
<validation validateIntegratedModeConfiguration="false" />
<modules>
<remove name="TelemetryHttpModule" />
<add name="TelemetryHttpModule" type="OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule" preCondition="managedHandler" />
</modules>
</system.webServer>
Note
applicationHost.config
is located in%SystemDrive%\Windows\system32\inetsrv\config
. Below is an example where you can add the module to set it for all ASP.NET application running in Integrated Pipeline Mode:
<location path="" overrideMode="Allow">
<system.webServer>
<modules>
<add name="TelemetryHttpModule" type="OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule" preCondition="managedHandler" />
</modules>
</system.webServer>
</location>
Note After applying above changes you can check whether
opentelemetry modules
are loaded by usingappcmd
command which can be found under%SystemDrive%\Windows\system32\inetsrv
. Following example shows invocation forWebDemo\
application:
appcmd list modules /app.name:"WebDemo/"
and correct result:
MODULE "TelemetryHttpModule" ( type:OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, OpenTelemetry.Instrumentation.AspNet.TelemetryHttpModule, preCondition:managedHandler )
Note Remember to restart IIS after making configuration changes. You can do it by executing
iisreset.exe
.
For ASP.NET application you can configure the most common OTEL_
settings
(like OTEL_SERVICE_NAME
) via appSettings
in Web.config
.
If a service name is not explicitly configured, one will be generated for you.
If the application is hosted on IIS in .NET Framework this will use
SiteName\VirtualDirectoryPath
ex: MySite\MyApp
For ASP.NET Core application you can use
the <environmentVariable>
elements inside the <aspNetCore>
block of your Web.config
file
to set configuration via environment variables.
You can add the <environmentVariables>
in applicationHost.config
to set environment variables for given application pools.
For IIS versions older than 10.0, you can consider creating a distinct user, set its environment variables and use it as the application pool user.
Consider setting common environment variables,
for all applications deployed to IIS
by setting the environment variables for
W3SVC
and WAS
Windows Services as described in windows-service-instrumentation.md.