如何从虚拟机连接 C# 和 MySQL？

Question

I setup a Linux virtual machine on Azure and deployed an Apache web server and MySQL. I have a C# application which I want to connect with the MySQL database from my virtual machine. I installed the MySQL connector and followed tutorials like this:

   string connString = "Database=Virtual Machine IP;port=3306;username=root;password=;database=testing";
            MySqlConnection conn = new MySqlConnection(connString);
            MySqlCommand command = conn.CreateCommand();
            command.CommandText = "Select * from Company";
            try
            {
                Console.WriteLine("Connecting to MySQL...");
                conn.Open();               
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            MySqlDataReader reader = command.ExecuteReader();
            while (reader.Read())
            {
                Console.WriteLine(reader["CompanyID"].ToString());
            }
            Console.ReadLine();

But it's not working as I receive this error: "Unable to connect to any of the specified MySQL hosts.", so the connection was not successfully, does anyone know how to do it?

PS I tried the code with my database from the localhost and it worked.

Answer 1

For the error, you probably need to enable the MySQL port 3306 in the inbound port rule of NSG. See this document: How to open ports to a virtual machine with the Azure portal .

For example, add the port 3306 in the destination port ranges and add your client public IP address to the Source IP addresses in the virtual network---networking---inbound port rules.