部署Asp.net Core 项目发生502.5 或者500 没有其他提示信息

      最近将公司原来.NetCore 1.6的项目升级到.net Core 2.0首先发生 502.5的错误,包括IIS日志,Windows应用程序日志都没有记录问题始终解决不了,首先看看官网给出的解决方案:

https://docs.microsoft.com/zh-cn/aspnet/core/host-and-deploy/iis/index?tabs=aspnetcore2x#common-errors

      1.安装DotNetCore.2.0.0-WindowsHosting.exe 和 Microsoft Visual C++ 2015 Redistributable 之后运行以下

//CMD命令窗口用管理员权限打开
   net stop was /y  
   net start w3svc
//这两句执行的结果是重启IIS服务,或者重启服务器是同样的效果

       2.重新刷新网页还是502.5,或者500程序没有任何提示信息,因为.net core的站点服务是托管的

       3.解决这个问题的关键首先是要弄清楚主机是缺少必须的Windows程序,还是程序本身报错,比如最后才弄清楚程序运行错误导致了502.5

Application startup exception: System.BadImageFormatException: Could not load file or assembly 'System.Runtime.CompilerServices.Unsafe, Version=4.0.3.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. Reference assemblies should not be loaded for execution.  They can only be loaded in the Reflection-only loader context. (Exception from HRESULT: 0x80131058)
File name: 'System.Runtime.CompilerServices.Unsafe, Version=4.0.3.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' ---> System.BadImageFormatException: Cannot load a reference assembly for execution.
   at Microsoft.Extensions.Primitives.InplaceStringBuilder.Append(String s, Int32 offset, Int32 count)
   at Microsoft.Net.Http.Headers.DateTimeFormatter.ToRfc1123String(DateTimeOffset dateTime, Boolean quoted)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.DateHeaderValueManager.SetDateValues(DateTimeOffset value)
   at Microsoft.AspNetCore.Server.Kestrel.Core.KestrelServer.CreateServiceContext(IOptions`1 options, ILoggerFactory loggerFactory)
   at Microsoft.AspNetCore.Server.Kestrel.Core.KestrelServer..ctor(IOptions`1 options, ITransportFactory transportFactory, ILoggerFactory loggerFactory)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, ServiceProvider provider)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScoped(ScopedCallSite scopedCallSite, ServiceProvider provider)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
   at Microsoft.AspNetCore.Hosting.Internal.WebHost.EnsureServer()
   at Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication()

        4.所以我们要代开站点自动记录日志的功能,在发布的站点下找到web.conig文件按照如下配置

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <system.webServer>
    <handlers>
      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModule" resourceType="Unspecified" />
    </handlers>
    <aspNetCore processPath="%LAUNCHER_PATH%" 
        arguments="%LAUNCHER_ARGS%" 
        stdoutLogEnabled="false" 
        stdoutLogFile=".logsstdout" />//注意这个路径站点要有写的权限
  </system.webServer>
</configuration>

          5.运行站点之后注意查看.logsstdout下的日志,基本能够知道托管站点在运行过程中,到底发生了什么错误!

           WebConfig配置细节请参考这里!