c＃httpclient无法从传输连接中读取数据：现有连接被远程主机强行关闭

Question

我有一个.NET 6控制台应用程序，该应用程序浏览了网站列表，并检查有关SSL证书或即将到来的任何问题的任何问题。它适用于所有网站，除了托管在Azure上的夫妇之外。对于这些网站，当本地调试时，所有内容都按预期工作。但是，当控制台应用程序在Windows 2012服务器上运行时，HTTP GET请求失败了9/10次，此例外：

System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception. ---> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.. ---> System.Net.Sockets.SocketException (10054): 

这些是我代码中的两个主要方法：

        async Task<CertStatus> SendRequest(string url)
        {
            _certStatus = new CertStatus
            {
                URL = url,
                Success = false
            };

            var handler = new HttpClientHandler();

            handler.ServerCertificateCustomValidationCallback = ServerCertificateCustomValidation;


            var client = new HttpClient(handler);

            try
            {
                var response = await client.GetAsync(url);

                response.EnsureSuccessStatusCode();

                _certStatus.Success = true;
            }
            catch (HttpRequestException ex)
            {
                _certStatus.ErrorMessage = ex.Message;
            }

            handler.Dispose();
            client.Dispose();

            var retval = _certStatus;

            return retval;
        }

        static bool ServerCertificateCustomValidation(HttpRequestMessage requestMessage, X509Certificate2? certificate, X509Chain? chain, SslPolicyErrors sslErrors)
        {
            if(_certStatus != null && certificate != null)
            {
                _certStatus.ExpireDate = DateTime.Parse(certificate.GetExpirationDateString());
            }


            Console.WriteLine($"Requested URI: {requestMessage.RequestUri}");
            Console.WriteLine($"Effective date: {certificate?.GetEffectiveDateString()}");
            Console.WriteLine($"Exp date: {certificate?.GetExpirationDateString()}");
            Console.WriteLine($"Issuer: {certificate?.Issuer}");
            Console.WriteLine($"Subject: {certificate?.Subject}");

            Console.WriteLine($"Errors: {sslErrors}");
            return sslErrors == SslPolicyErrors.None;
        }

我尝试将连接设置为TRUE

client.DefaultRequestHeaders.ConnectionClose = true;

增加超时

client.Timeout = TimeSpan.FromSeconds(120);

并设置设置SSL协议to TLS 1.2即使是.NET 6.0，但我认为这

System.Net.ServicePointManager.SecurityProtocol |= System.Net.SecurityProtocolType.Tls12;

对我可以尝试的是其他想法吗？对我来说，有时会成功并且有时失败，这对我来说很奇怪。 Windows Task Scheduler每天运行此控制台应用程序，并且在这些运行过程中始终失败。但是，当手动运行EXE时，有时会成功