deployed next.js app to azure static web app giving issues: backend call failure , insights log error: System.InvalidOperationException: atMono.Unix.UnixFileSystemInfo.AssertValid

Prem Murmu 10

I tried to find issue with insights, error is as follow:

System.InvalidOperationException: at
Mono.Unix.UnixFileSystemInfo.AssertValid
(Mono.Posix.NETStandard, Version=1.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51) at Microsoft.Azure.WebJobs.Script.Workers.
Http.HttpWorkerProcess.AssignUserExecute
PermissionsIfNotExists (Microsoft.Azure.WebJobs.Script, Version=4.21.0.0, Culture=neutral, PublicKeyToken=null: /src/azure-functions-host/src/WebJobs.Script/Workers

/Http/HttpWorkerProcess.cs:75

Please advise the solution for it . thanks!

Grmacjon-MSFT 16,011 Reputation points

2023-07-13T23:17:34.8433333+00:00
Hi @Prem Murmu

is this a Static Next.js or Hybrid Next.js application? when did you start facing this issue?

The error message you provided suggests that there is an issue with the permissions of the user executing the Azure Functions host process. Specifically, the error message indicates that the process is unable to assign user execute permissions to a file or directory.

To fix this issue, you can try the following steps:

Check the permissions of the files and directories in your application. Make sure that the user executing the Azure Functions host process has the necessary permissions to read, write, and execute the files and directories.

Check the user account that is running the Azure Functions host process. Make sure that the user account has the necessary permissions to access the files and directories in your application.

Check the configuration of your Azure Static Web App. Make sure that the configuration is correct and that the Azure Functions host process is running with the correct user account and permissions.

Check the logs of your Azure Static Web App for any additional error messages or warnings that may provide more information about the issue.

Hope that helps.

-Grace
Chris Canossi 15 Reputation points

2023-08-09T21:34:52.17+00:00
Hi @Prem Murmu, @Grmacjon-MSFT , and community,

I've encountered a similar issue with my Azure Static Web App running Next.js. After facing the "Backend call failure" and investigating via Application Insights, my logs mirror the error detailed by Prem:

Exception: "Path doesn't exist" - App Insight:

System.InvalidOperationException: at Mono.Unix.UnixFileSystemInfo.AssertValid (Mono.Posix.NETStandard, Version=1.0.0.0, Culture=neutral, PublicKeyToken=cc7xxxxxx2ddd51) at Microsoft.Azure.WebJobs.Script.Workers.Http.HttpWorkerProcess.AssignUserExecutePermissionsIfNotExists (Microsoft.Azure.WebJobs.Script, Version=4.21.0.0, Culture=neutral, PublicKeyToken=null: /src/azure-functions-host/src/WebJobs.Script/Workers/Http/HttpWorkerProcess.cs:75)

Browser:

However, I've observed that simply refreshing the page often leads to the site loading normally without any error. This behavior makes me believe it might not be strictly related to file or directory permissions. Instead, it feels more like a sporadic or timing-related problem, perhaps with the underlying infrastructure or the way Next.js interacts with it.

Has anyone experienced a similar behavior and found more specific diagnostics or solutions? I appreciate any additional insights on this.

Thank you!
-Chris
Flo 0 Reputation points

2023-11-02T05:16:50.5333333+00:00

Hi, I'm facing the same exact issue as Chris.
I'm in Standalone mode, any insight how to fix this ?
Simon Rijsewijk 0 Reputation points

2023-11-14T12:23:43.8033333+00:00

I'm experiencing the same issue.
Christian Ayala 0 Reputation points

2023-12-07T16:28:16.2633333+00:00
I was also experiencing this issue. I am deploying a NextJS Standalone application, with getServerSideProps running for a few pages of the application. There were a few things that may be tied to this:

This issue started appearing when I associated a Custom Domain to the Static Web App. When loading the app using the custom domain, every so often it would give the same Backend call failure and refreshing the page would fix it (so it doesn't seem to be an issue with the custom domain mapping on the DNS side of things). I did not see this behavior when using the auto-generated SWA URL, which I had previously been using for a few months of active development + testing.

Originally the app was using the free hosting plan on SWA. I upgraded to the Standard plan ($9/month) and have not seen the issue appear again. I don't know what Azure may be doing behind the scenes, but paying for the standard plan seemed to fix the issue for now.

This only appeared on pages that are server-rendered (getServerSideProps), not static. Which makes sense for a backend call failure.

Hope this helps. Unfortunate that the fix in my case was to pay Azure, especially since this issue appeared in a test app that worked just fine on the free plan.
Matteo Mario Cossu 21 Reputation points

2024-03-28T16:02:52.4566667+00:00

Same for Next.js 14.10.0 with App routing on Azure Static Web App Free Plan.
Came out randomly, lasted a minute, then back to normal...