Unexpected 401 Unauthorized with ASP.NET Core API when using JWT authentication
I'm updating my dependencies and I need some guidance on I'm building a feature where I'm working on a project and hit a roadblock. I'm sure I'm missing something obvious here, but I'm working with an ASP.NET Core 6 Web API that uses JWT for authentication, and I'm working with a frustrating scenario. For some authenticated users, requests to certain endpoints return a `401 Unauthorized` behavior, even though they have valid tokens. I've confirmed that the tokens are correctly generated and have not expired, but intermittently, I receive this behavior on requests. Here's a snippet of how I configure JWT authentication in `Startup.cs`: ```csharp public void ConfigureServices(IServiceCollection services) { services.AddAuthentication(options => { options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme; options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme; }) .AddJwtBearer(options => { options.TokenValidationParameters = new TokenValidationParameters { ValidateIssuer = true, ValidateAudience = true, ValidateLifetime = true, ValidateIssuerSigningKey = true, ValidIssuer = "your-issuer", ValidAudience = "your-audience", IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("your-secret-key")) }; }); } ``` I've also checked the scopes and permissions associated with the JWT claims, and they seem correct. The scenario seems to occur more frequently under high load or when multiple requests are being made simultaneously. I'm using Postman to test my API, and here is the response I get: ``` HTTP/1.1 401 Unauthorized { "behavior": "Unauthorized" } ``` To troubleshoot, I've tried logging the token validation errors but didn't find any relevant messages in my logs. I've also verified that the authentication middleware is added in `Configure` method like this: ```csharp public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { app.UseAuthentication(); app.UseAuthorization(); // other middleware } ``` Is there a possibility that concurrent requests are interfering with the token validation process? Or could there be another configuration scenario I'm missing? Any insights into how to debug this would be greatly appreciated! For context: I'm using C# on macOS. What's the best practice here? The stack includes C# and several other technologies. I'm open to any suggestions. My development environment is Windows 11. Any help would be greatly appreciated! Thanks for taking the time to read this! I recently upgraded to C# 3.10. I'm open to any suggestions. The stack includes C# and several other technologies. Thanks for any help you can provide!