Is web server logging supported for all types of app services?

Question

Is web server logging supported for all types of app services?

Rachana Pole 10

Hi team,

Which app services ( web app, function app, logic app ) are Web server logging, i.e, HTTP logging supported?
1. If yes, for which ones, and is there any further criteria on specific app service for which it is supported?
2. Provide Azure documentation reference on what is supported and how to configure it with the latest steps.
The App Service logs tab is grayed out for the app services where clicking does not work. When trying to open in a new tab, it does open. Is this a bug?

Even if console is grayed out and no option is provided for few of apps, using below CLI, the config is toggling. Why?

      az webapp log config --name <App name> --resource-group <Resource Group Name> --web-server-logging filesystem

Shree Hima Bindu Maganti 4,150 Reputation points Microsoft External Staff

2025-04-29T11:02:18.2866667+00:00

Hi @Rachana Pole
Web server logging, also known as HTTP logging, is supported for Windows-based App Services, especially for Web Apps. However, it isn't specifically mentioned for Function Apps or Logic Apps in the provided context.

For Web Apps, you can enable web server logging through the Azure portal by selecting the appropriate options under the App Service logs settings. The configuration steps include choosing the storage location for logs (either File System or Azure Storage blobs) and setting the retention period.

Regarding the issue with the App Service logs tab being grayed out, this could be due to a user interface bug or a permissions issue. If the logs tab is not functioning as expected, it may be helpful to check user permissions.

As for the CLI command you mentioned, it seems to allow toggling the configuration for web server logging even if the UI options are grayed out. This could be because the CLI has different permissions or access levels compared to the Azure portal interface.
Enable diagnostic logging for apps in Azure App Service

Enable web server logging
https://learn.microsoft.com/en-us/azure/azure-monitor/reference/supported-logs/microsoft-web-sites-logs
Let me know if you have any further queries.

Bhargavi Naragani 3,165 Microsoft External Staff

Hi @Rachana Pole,

Web Server Logging (HTTP Logging) Support by App Service Type:

App Service Type	Web Server Logging Supported?	Notes
Web App (Windows)	Yes	Fully supported. Can be configured via Azure Portal or CLI.
Web App (Linux)	Yes	Supported, but with differences, logs are typically sent to `stdout/stderr` and accessed via App Service logs or Azure Monitor.
Function App	Partially	Logging is supported, but not through traditional web server logging. Use Application Insights, `ILogger`, or Azure Monitor Logs.
Logic App	No	Logic Apps have their own diagnostics and monitoring pipeline; web server logging does not apply here.

Sometimes the App Service logs tab appears grayed out in the portal, even when logging is technically supported. This often happens due to:

Permissions issues (e.g., Reader role vs Contributor role).

Platform mismatches (e.g., trying to enable File System logging on a Linux-based Web App where only stdout/stderr logging is available).

UI bugs or portal latency, where the portal doesn’t refresh the available options correctly.

On the other hand, Azure CLI interacts directly with the App Service management API, bypassing the UI. This is why you can still configure web server logging using the CLI (az webapp log config), even if the portal UI appears unresponsive or restricted.

Here’s your command again, which works correctly:

az webapp log config --name <App Name> --resource-group <Resource Group Name> --web-server-logging filesystem

This CLI command is valid for Windows Web Apps only. For Linux apps, logging is handled differently (logs go to the console and are picked up by Azure Monitor).

Kindly refer to the below documentations for better understanding:
https://learn.microsoft.com/en-us/azure/app-service/troubleshoot-diagnostic-logs#overview-of-logging-types
https://learn.microsoft.com/en-us/azure/azure-monitor/app/codeless-app-service?tabs=aspnetcore#enabling-logging
https://learn.microsoft.com/en-us/azure/azure-functions/functions-monitoring
https://learn.microsoft.com/en-us/cli/azure/webapp/log?view=azure-cli-latest

Hope this information is helpful, let me know if you have any further queries.

Laxman Reddy Revuri 4,000 Reputation points Microsoft External Staff

2025-04-30T21:59:05.2933333+00:00

Hi @Rachana Pole,
We haven’t heard from you on the last response and was just checking back to see if you have a resolution yet. In case if you have any resolution please do share that same with the community as it can be helpful to others. Otherwise, will respond with more details and we will try to help.

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Shree Hima Bindu Maganti 4,150 Reputation points Microsoft External Staff

2025-04-29T11:02:18.2866667+00:00

Hi @Rachana Pole
Web server logging, also known as HTTP logging, is supported for Windows-based App Services, especially for Web Apps. However, it isn't specifically mentioned for Function Apps or Logic Apps in the provided context.

For Web Apps, you can enable web server logging through the Azure portal by selecting the appropriate options under the App Service logs settings. The configuration steps include choosing the storage location for logs (either File System or Azure Storage blobs) and setting the retention period.

Regarding the issue with the App Service logs tab being grayed out, this could be due to a user interface bug or a permissions issue. If the logs tab is not functioning as expected, it may be helpful to check user permissions.

As for the CLI command you mentioned, it seems to allow toggling the configuration for web server logging even if the UI options are grayed out. This could be because the CLI has different permissions or access levels compared to the Azure portal interface.
Enable diagnostic logging for apps in Azure App Service

Enable web server logging
https://learn.microsoft.com/en-us/azure/azure-monitor/reference/supported-logs/microsoft-web-sites-logs
Let me know if you have any further queries.
Laxman Reddy Revuri 4,000 Reputation points Microsoft External Staff

2025-04-30T21:59:05.2933333+00:00

Hi @Rachana Pole,
We haven’t heard from you on the last response and was just checking back to see if you have a resolution yet. In case if you have any resolution please do share that same with the community as it can be helpful to others. Otherwise, will respond with more details and we will try to help.

Answer 1

Hi Rachana Pole,

Thanks for raising this. I understand the situation you are facing currently, when things like the "App Service logs" tab are grayed out but the CLI still works. That can definitely seem inconsistent.

Azure portal interface is designed to surface only the options that are compatible with the app's underlying platform and configuration. So, if you are using something like a Linux-based Web App, a Function App, or a service where traditional web server logging isn't fully supported, the portal may gray out those logging options to prevent misconfiguration. However, that doesn't necessarily mean the functionality is completely blocked.

The Azure CLI, on the other hand, interacts directly with the backend API. It doesn't rely on portal UI checks or constraints, which is why you're able to configure logging through CLI commands even when the UI doesn't respond. This is expected behavior, not a bug. It also means that in some cases, the CLI is your best tool for enabling settings that the portal doesn't currently expose due to platform-specific rules.

Please check these references:

If you are still facing the issue about which logging options apply to your specific app or platform, feel free to share more details about the app type and OS. I’d be happy to help check what’s supported in your case.

Hope it helps!

Please do not forget to click "Accept the answer” and Yes wherever the information provided helps you, this can be beneficial to other community members.

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Is web server logging supported for all types of app services?

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