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我最近开始使用 AWS 的 Cassandra Managed Service 产品，并尝试以编程方式连接到 AWS 在其文档中显示的示例密钥表。我已经下载了 Cassandra c# 驱动程序并获得了生成的服务凭据。我现在遇到的问题是连接到集群（cluster.Connect()）。我尝试在 .Connect 中使用各种不同的集群名称，但没有运气。任何人都知道集群名称应该是，或者在哪里可以找到它？另外，还有什么我没有的吗？这是否需要 TLS 连接编程才能工作？

我收到的错误是“找不到主机”：

using System;
using Cassandra;

namespace SampleConnect
{
    class Program
    {
        static void Main(string[] args)
        {
            var cluster = Cluster.Builder()
                                 .AddContactPoints("cassandra.us-east-2.amazonaws.com")
                                 .WithPort(9142)
                                 //.WithLoadBalancingPolicy(new DCAwareRoundRobinPolicy("AWS_VPC_AP_SOUTHEAST_2"))
                                 .WithAuthProvider(new PlainTextAuthProvider("credential username", "crededential password"))
                                 .Build();

            // Connect to the nodes using a keyspace
            var session = cluster.Connect();

            // Get name of a Cluster
            Console.WriteLine("The cluster's name is: " + cluster.Metadata.ClusterName);

            // Execute a query on a connection synchronously
            var rs = session.Execute("SELECT * FROM tutorialtable");

            // Iterate through the RowSet
            foreach (var row in rs)
            {
                var value = row.GetValue<string>("keyspace_name");
                Console.WriteLine(value);
                // Do something with the value
            }
        }
    }
}

错误信息：

尝试查询的所有主机都失败（尝试了 3.17.137.4:9042: SocketException '连接尝试失败，因为连接方在一段时间后没有正确响应，或者建立连接失败，因为连接的主机没有响应。'）

堆栈跟踪：

   at Cassandra.Connections.ControlConnection.<Connect>d__39.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()
   at Cassandra.Connections.ControlConnection.<InitAsync>d__36.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()
   at Cassandra.Tasks.TaskHelper.<WaitToCompleteAsync>d__10.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Cassandra.Cluster.<Cassandra-SessionManagement-IInternalCluster-OnInitializeAsync>d__50.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at Cassandra.ClusterLifecycleManager.<InitializeAsync>d__3.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()
   at Cassandra.Cluster.<Cassandra-SessionManagement-IInternalCluster-ConnectAsync>d__47`1.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at Cassandra.Cluster.<ConnectAsync>d__46.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Cassandra.Tasks.TaskHelper.WaitToComplete(Task task, Int32 timeout)
   at Cassandra.Tasks.TaskHelper.WaitToComplete[T](Task`1 task, Int32 timeout)
   at Cassandra.Cluster.Connect(String keyspace)
   at Cassandra.Cluster.Connect()
   at LoadBusinessData.Program.Main(String[] args) in Program.cs:line 20
4

1 回答 1

2

您需要使用 SSL/TLS。所以你的直觉是正确的。

于 2020-01-06T22:48:23.480 回答