Automatic instrumentation fails after setup about dd-trace-dotnet

[dd-caleb]

It looks like the agent is more restrictive in the format its allowed to receive than what the tracer is producing. I think we can add code to where the tracer sends spans to remove nil strings or set them to the empty string.

To disable automatic instrumentation you have to remove an environment variable. (SET COR_ENABLE_PROFILING=0) We should document this, but we should also provide a way to configure this through the apm section of the datadog agent config yaml. We should also limit the amount we log on errors, since the trace agent being down is entirely possible under normal usage.

@vasiliy0 besides the noise in the logs, did this break the application? Or did IIS continue to work properly?

[vasiliy0]

@dd-caleb thank you for quick response. I will try your suggestions to turn off instrumentation.

Regarding the application, it works as intended without breaking. The excessive logging might be the issue though, if someone is using cloud log aggregators with limited number of events allowed.

What can be an ETA on the new version with fixed tracer?

[lucaspimentel]

Regarding the environment variables, the installer sets these only for the IIS service, not system-wide, otherwise we would attach the profiler to every .NET process in the host. You can find the Environment values in the Windows Registy at:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W3SVC

Remember also that IIS won't recognize changes to the environment variables until the host is rebooted. Instead of modifying these values by hand, uninstalling the msi will remove the environment variables and delete the files installed into the GAC and Program Files folder.

If you don't have a UI (e.g. Windows Server Core), you can use the following commands from an administrator command prompt:

msiexec.exe /qn /norestart /uninstall DatadogDotNetTracing-0.3.0-x64.msi

If you don't have the msi file handy, use the Product Code:

msiexec.exe /qn /norestart /uninstall {359AD4E1-5CD3-4920-A5BF-2A12DD812D1C}

[vasiliy0]

@lucaspimentel thank you for your comment.

Removed tracer and ran iisreset, logging errors stopped. Seems like it is enough for IIS to update environment variables.

[lucaspimentel]

@vasiliy0: this bug is fixed and will be included in the next beta release. Thanks again for reporting it!

[lucaspimentel]

@vasiliy0: We released 0.3.1-beta which should fix these errors. Thanks again.