无法从SSMS连接至Cloud SQL（SQL Server）实例求助

已尝试的操作：

• 关闭防火墙，排除对公网IP和端口的拦截
• 确认SQL Server Browser服务已启用
• 反复验证使用SQL Server认证，用户名和密码无误

但仍无法连接目标SQL Server实例，报错信息如下：

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无法连接到 34.131.103.91。

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建立与SQL Server的连接时出现与网络相关的或特定于实例的错误。未找到服务器或无法访问服务器。请验证实例名称是否正确，并且SQL Server已配置为允许远程连接。(provider: 命名管道提供程序, error: 40 - 无法打开到SQL Server的连接) (Framework Microsoft SqlClient Data Provider)

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错误编号: 53
严重级别: 20
状态: 0


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程序位置:

   在 Microsoft.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
   在 Microsoft.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
   在 Microsoft.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, Boolean withFailover, Boolean isFirstTransparentAttempt, SqlAuthenticationMethod authType, String certificate, ServerCertificateValidationCallback serverCallback, ClientCertificateRetrievalCallback clientCallback, Boolean useOriginalAddressInfo, Boolean disableTnir)
   在 Microsoft.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, SecureString newSecurePassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, Boolean withFailover, Boolean isFirstTransparentAttempt, Boolean disableTnir)
   在 Microsoft.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString connectionOptions, SqlCredential credential, TimeoutTimer timeout)
   在 Microsoft.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(TimeoutTimer timeout, SqlConnectionString connectionOptions, SqlCredential credential, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance)
   在 Microsoft.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, ServerCertificateValidationCallback serverCallback, ClientCertificateRetrievalCallback clientCallback, DbConnectionPool pool, String accessToken, SqlClientOriginalNetworkAddressInfo originalNetworkAddressInfo, Boolean applyTransientFaultHandling)
   在 Microsoft.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
   在 Microsoft.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup, DbConnectionOptions userOptions)
   在 Microsoft.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   在 Microsoft.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   在 Microsoft.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   在 Microsoft.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   在 Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry, SqlConnectionOverrides overrides)
   在 Microsoft.Data.SqlClient.SqlConnection.Open(SqlConnectionOverrides overrides)
   在 Microsoft.Data.SqlClient.SqlConnection.Open()
   在 Microsoft.SqlServer.Management.SqlStudio.Explorer.ObjectExplorerService.ValidateConnection(UIConnectionInfo ci, IServerType server)
   在 Microsoft.SqlServer.Management.UI.ConnectionDlg.Connector.ConnectionThreadUser()

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未找到网络路径

进一步排查建议 #

• 检查SQL Server远程连接配置：打开SQL Server配置管理器，确保SQL Server网络配置下的TCP/IP协议已启用；在TCP/IP属性的「IP地址」标签中，确认TCP端口设置正确（默认1433），同时进入SQL Server实例属性，勾选「允许远程连接到此服务器」。
• 验证端口映射有效性：如果服务器位于局域网内，确认路由器已正确将公网端口转发至SQL Server所在机器的对应端口（如1433），且映射规则未被禁用。
• 测试网络连通性：使用命令行工具测试端口可达性：
  • Windows：telnet 34.131.103.91 1433 或 Test-NetConnection 34.131.103.91 -Port 1433
  • Linux/macOS：nc -zv 34.131.103.91 1433
• 确认SQL Server实例状态：确保目标SQL Server实例服务处于运行状态，而非仅SQL Server Browser服务运行。
• 检查连接字符串格式：若使用客户端连接，确认连接字符串正确指定端口或实例名，例如：34.131.103.91,1433（默认实例）或34.131.103.91\你的实例名（命名实例）。

内容的提问来源于stack exchange，提问作者Ibraheem Haseeb