连接到 Redshift 集群时出错 - Npgsql.PostgresException: 28000: no pg_hba.conf entry for host

Posted 2023-03-30

【中文标题】连接到 Redshift 集群时出错 - Npgsql.PostgresException: 28000: no pg_hba.conf entry for host

【英文标题】：Error connecting to Redshift Cluster - Npgsql.PostgresException: 28000: no pg_hba.conf entry for host

【发布时间】：2020-05-18 11:12:04

【问题描述】：

我正在尝试从 C# 连接到 AWS Redshift 并执行一个简单的查询：

public void GetData()

    NpgsqlConnectionStringBuilder builder = new NpgsqlConnectionStringBuilder();
    builder.Host = "myhostname";
    builder.Port = 5439;
    builder.Database = "mydb";
    builder.Username = "myusername";
    builder.Password = "mypassword";
    builder.ServerCompatibilityMode = ServerCompatibilityMode.Redshift;

    using (var conn = new NpgsqlConnection(builder.ConnectionString))
    
        conn.Open();
        if (conn.State == ConnectionState.Open)
        
            using (var cmd = new NpgsqlCommand())
            
                cmd.Connection = conn;
                cmd.CommandText = "SELECT TOP 10 field FROM example;";

                using (var reader = cmd.ExecuteReader())
                
                    while (reader.Read())
                    
                        Console.WriteLine(reader.GetString(0));
                    
                
            
        
    

尝试建立连接时，我得到：Npgsql.PostgresException: 28000: no pg_hba.conf entry for host。在同一台机器上，我可以使用 JetBrains DataGrip 使用相同的凭据连接到集群。

【问题讨论】：

尝试将 SslMode 设置为 required，并将 TrustServerCertificate 设置为 true，如 here 所述

【参考方案1】：

This 问题几乎相同，但不是手动创建连接字符串，而是使用构建器。所以这里是代码：

NpgsqlConnectionStringBuilder builder = new NpgsqlConnectionStringBuilder();
builder.TrustServerCertificate = true;
builder.SslMode = SslMode.Required;