iis 连接不到mysql

ping <MySQL服务器IP地址>

CREATE USER 'iisuser'@'%' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON *.* TO 'iisuser'@'%';
FLUSH PRIVILEGES;

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using MySql.Data.MySqlClient;

namespace IISMySQLExample
{
    public class Startup
    {
        public IConfiguration Configuration { get; }

        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public void ConfigureServices(IServiceCollection services)
        {
            string connectionString = Configuration.GetConnectionString("DefaultConnection");
            services.AddControllersWithViews();
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();

            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}

{
  "ConnectionStrings": {
    "DefaultConnection": "Server=<MySQL服务器IP地址>;Database=<数据库名称>;Uid=iisuser;Pwd=password;"
  }
}