I have an error (Failed to start a new language worker for runtime: dotnet-isolated) after deploying the isolated Azure Function developed in dotnet 7

Question

I have an error after deploying the isolated Azure Function V4 developed in Dotnet 7. error custom details are as below:

{"FormattedMessage":"Failed to start a new language worker for runtime: dotnet-isolated.","LogLevel":"Error","prop__{OriginalFormat}":"Failed to start a new language worker for runtime: dotnet-isolated.","HostInstanceId":"e121133c-fce7-40a6-8158-a412d520dac7","Category":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher","ProcessId":"24"}
Complete details are as below:

[{"id":"45214701","outerId":"0","type":"System.Threading.Tasks.TaskCanceledException","message":"A task was canceled.","parsedStack":[{"level":0,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":1,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":2,"method":"Microsoft.Azure.WebJobs.Script.Grpc.GrpcWorkerChannel+<StartWorkerProcessAsync>d__53.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script.Grpc, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":271,"fileName":"/src/azure-functions-host/src/WebJobs.Script.Grpc/Channel/GrpcWorkerChannel.cs"},{"level":3,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":4,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":5,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__51.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":154,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":6,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":7,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":8,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":9,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__50.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":146,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":10,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":11,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":12,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":13,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__49.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":137,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":14,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":15,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":16,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<>c__DisplayClass56_0+<<StartWorkerProcesses>b__0>d.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":229,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"}],"severityLevel":"Error"}]
0
{"id":"45214701","outerId":"0","type":"System.Threading.Tasks.TaskCanceledException","message":"A task was canceled.","parsedStack":[{"level":0,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":1,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":2,"method":"Microsoft.Azure.WebJobs.Script.Grpc.GrpcWorkerChannel+<StartWorkerProcessAsync>d__53.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script.Grpc, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":271,"fileName":"/src/azure-functions-host/src/WebJobs.Script.Grpc/Channel/GrpcWorkerChannel.cs"},{"level":3,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":4,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":5,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__51.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":154,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":6,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":7,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":8,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":9,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__50.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":146,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":10,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":11,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":12,"method":"System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":13,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<InitializeJobhostLanguageWorkerChannelAsync>d__49.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":137,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"},{"level":14,"method":"System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":15,"method":"System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess","assembly":"System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e","line":0},{"level":16,"method":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher+<>c__DisplayClass56_0+<<StartWorkerProcesses>b__0>d.MoveNext","assembly":"Microsoft.Azure.WebJobs.Script, Version=4.14.0.0, Culture=neutral, PublicKeyToken=null","line":229,"fileName":"/src/azure-functions-host/src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs"}],"severityLevel":"Error"}
exception
{"FormattedMessage":"Failed to start a new language worker for runtime: dotnet-isolated.","LogLevel":"Error","prop__{OriginalFormat}":"Failed to start a new language worker for runtime: dotnet-isolated.","HostInstanceId":"e121133c-fce7-40a6-8158-a412d520dac7","Category":"Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher","ProcessId":"24"}
Category
Microsoft.Azure.WebJobs.Script.Workers.Rpc.RpcFunctionInvocationDispatcher
FormattedMessage
Failed to start a new language worker for runtime: dotnet-isolated.
HostInstanceId
e121133c-fce7-40a6-8158-a412d520dac7
LogLevel
Error
ProcessId
24
prop__{OriginalFormat}
Failed to start a new language worker for runtime: dotnet-isolated.
PC
0. 0.0.0
devtest1006
d69eace19f1da88aefa0be947bc6851cb68885c32eebdef6f5ccaba71e782ab8
341b8655-67f8-4f11-b678-70936cd95279
devntdinfafl1006
96481cff-18a0-417e-9273-3c93db63d073
azurefunctions: 4.14.0.0
91faec76-7677-11ed-ab3b-d1cf6d835441
1

What would be the soultion. Is there something I have missed?

Answer 1

Hello @Varinderpal Singh Malhi - Thanks for reaching out and posting on MS Q&A. Could you verify the correct value for the FUNCTIONS_WORKER_RUNTIME setting? It should be set to dotnet-isolated, as stated in the doc:

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Answer 2

The issue is resolved. I had all the settings as per the documentation. The problem was the NuGet packages used in the solution. I was using Microsoft.WindowsAzure.Storage.blobs instead of Azure.Storage.Blobs. This replacement resolved the issue. Whenever the class was called ServiceWorker was failing and was not able to reload again and the error logged.