dotnet runtime_error ai_generated true

Microsoft.AspNetCore.Server.Kestrel.Core.BadHttpRequestException: Request body too large. The max request body size is 30000000 bytes.

ID: dotnet/kestrel-request-body-too-large

Also available as: JSON · Markdown · 中文

90%Fix Rate

89%Confidence

1Evidence

2023-02-14First Seen

Version Compatibility

Version	Status	Introduced	Deprecated	Notes
ASP.NET Core 6.0	active	—	—	—
ASP.NET Core 7.0	active	—	—	—
ASP.NET Core 8.0	active	—	—	—

Root Cause

The incoming HTTP request body exceeds the Kestrel server's configured maximum request body size limit, which defaults to ~28.6 MB (30,000,000 bytes) or can be customized via MaxRequestBodySize.

generic

中文

传入的 HTTP 请求正文超过了 Kestrel 服务器配置的最大请求正文大小限制，默认约为 28.6 MB（30,000,000 字节），或可通过 MaxRequestBodySize 自定义。

Official Documentation

https://learn.microsoft.com/en-us/aspnet/core/fundamentals/servers/kestrel/options

Workarounds

90% success Increase the limit for specific endpoints using the [RequestSizeLimit] attribute: [RequestSizeLimit(50_000_000)] public IActionResult Upload() { ... }
```
Increase the limit for specific endpoints using the [RequestSizeLimit] attribute: [RequestSizeLimit(50_000_000)] public IActionResult Upload() { ... }
```
95% success Configure Kestrel globally in Program.cs: builder.WebHost.ConfigureKestrel(options => options.Limits.MaxRequestBodySize = 50 * 1024 * 1024); // 50 MB
```
Configure Kestrel globally in Program.cs: builder.WebHost.ConfigureKestrel(options => options.Limits.MaxRequestBodySize = 50 * 1024 * 1024); // 50 MB
```

中文步骤

使用 [RequestSizeLimit] 属性增加特定端点的限制：[RequestSizeLimit(50_000_000)] public IActionResult Upload() { ... }

在 Program.cs 中全局配置 Kestrel：builder.WebHost.ConfigureKestrel(options => options.Limits.MaxRequestBodySize = 50 * 1024 * 1024); // 50 MB

Dead Ends

Common approaches that don't work:

80% fail
This disables the limit entirely, risking denial-of-service from large payloads.
70% fail
Kestrel checks the uncompressed size; compression does not bypass the limit.