Getting started with AD Connector

With AD Connector you can connect AWS Directory Service to your existing enterprise Active Directory. When connected to your existing directory, all of your directory data remains on your domain controllers. AWS Directory Service does not replicate any of your directory data.

AD Connector prerequisites

To connect to your existing directory with AD Connector, you need the following:

AWS IAM Identity Center prerequisites

If you plan to use IAM Identity Center with AD Connector, you need to ensure that the following are true:

For more information, see IAM Identity Center prerequisites in the AWS IAM Identity Center User Guide.

Multi-factor authentication prerequisites

To support multi-factor authentication with your AD Connector directory, you need the following:

For more information about using AD Connector with MFA, see Enabling multi-factor authentication for AD Connector.

Delegate privileges to your service account

To connect to your existing directory, you must have the credentials for your AD Connector service account in the existing directory that has been delegated certain privileges. While members of the Domain Admins group have sufficient privileges to connect to the directory, as a best practice, you should use a service account that only has the minimum privileges necessary to connect to the directory. The following procedure demonstrates how to create a new group called Connectors, delegate the necessary privileges that are needed to connect AWS Directory Service to this group, and then add a new service account to this group.

This procedure must be performed on a machine that is joined to your directory and has the Active Directory User and Computers MMC snap-in installed. You must also be logged in as a domain administrator.

Test your AD Connector

For AD Connector to connect to your existing directory, the firewall for your existing network must have certain ports open to the CIDRs for both subnets in the VPC. To test if these conditions are met, perform the following steps:

The following is the source code for the DirectoryServicePortTest application.

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;
using System.DirectoryServices.ActiveDirectory;
using System.Threading;
using System.DirectoryServices.AccountManagement;
using System.DirectoryServices;
using System.Security.Authentication;
using System.Security.AccessControl;
using System.Security.Principal;

namespace DirectoryServicePortTest
{
    class Program
    {
        private static List<int> _tcpPorts;
        private static List<int> _udpPorts;

        private static string _domain = "";
        private static IPAddress _ipAddr = null;

        static void Main(string[] args)
        {
            if (ParseArgs(args))
            {
                try
                {
                    if (_domain.Length > 0)
                    {
                        try
                        {
                            TestForestFunctionalLevel();

                            TestDomainFunctionalLevel();
                        }
                        catch (ActiveDirectoryObjectNotFoundException)
                        {
                            Console.WriteLine("The domain {0} could not be found.\n", _domain);
                        }
                    }

                    if (null != _ipAddr)
                    {
                        if (_tcpPorts.Count > 0)
                        {
                            TestTcpPorts(_tcpPorts);
                        }

                        if (_udpPorts.Count > 0)
                        {
                            TestUdpPorts(_udpPorts);
                        }
                    }
                }
                catch (AuthenticationException ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
            else
            {
                PrintUsage();
            }

            Console.Write("Press <enter> to continue.");
            Console.ReadLine();
        }

        static void PrintUsage()
        {
            string currentApp = Path.GetFileName(System.Reflection.Assembly.GetExecutingAssembly().Location);
            Console.WriteLine("Usage: {0} \n-d <domain> \n-ip \"<server IP address>\" \n[-tcp \"<tcp_port1>,<tcp_port2>,etc\"] \n[-udp \"<udp_port1>,<udp_port2>,etc\"]", currentApp);
        }

        static bool ParseArgs(string[] args)
        {
            bool fReturn = false;
            string ipAddress = "";

            try
            {
                _tcpPorts = new List<int>();
                _udpPorts = new List<int>();

                for (int i = 0; i < args.Length; i++)
                {
                    string arg = args[i];

                    if ("-tcp" == arg | "/tcp" == arg)
                    {
                        i++;
                        string portList = args[i];
                        _tcpPorts = ParsePortList(portList);
                    }

                    if ("-udp" == arg | "/udp" == arg)
                    {
                        i++;
                        string portList = args[i];
                        _udpPorts = ParsePortList(portList);
                    }

                    if ("-d" == arg | "/d" == arg)
                    {
                        i++;
                        _domain = args[i];
                    }

                    if ("-ip" == arg | "/ip" == arg)
                    {
                        i++;
                        ipAddress = args[i];
                    }
                }
            }
            catch (ArgumentOutOfRangeException)
            {
                return false;
            }

            if (_domain.Length > 0 || ipAddress.Length > 0)
            {
                fReturn = true;
            }

            if (ipAddress.Length > 0)
            { 
                _ipAddr = IPAddress.Parse(ipAddress); 
            }
            
            return fReturn;
        }

        static List<int> ParsePortList(string portList)
        {
            List<int> ports = new List<int>();

            char[] separators = {',', ';', ':'};

            string[] portStrings = portList.Split(separators);
            foreach (string portString in portStrings)
            {
                try
                {
                    ports.Add(Convert.ToInt32(portString));
                }
                catch (FormatException)
                {
                }
            }

            return ports;
        }

        static void TestForestFunctionalLevel()
        {
            Console.WriteLine("Testing forest functional level.");

            DirectoryContext dirContext = new DirectoryContext(DirectoryContextType.Forest, _domain, null, null);
            Forest forestContext = Forest.GetForest(dirContext);

            Console.Write("Forest Functional Level = {0} : ", forestContext.ForestMode);

            if (forestContext.ForestMode >= ForestMode.Windows2003Forest)
            {
                Console.WriteLine("PASSED");
            }
            else
            {
                Console.WriteLine("FAILED");
            }

            Console.WriteLine();
        }

        static void TestDomainFunctionalLevel()
        {
            Console.WriteLine("Testing domain functional level.");

            DirectoryContext dirContext = new DirectoryContext(DirectoryContextType.Domain, _domain, null, null);
            Domain domainObject = Domain.GetDomain(dirContext);

            Console.Write("Domain Functional Level = {0} : ", domainObject.DomainMode);

            if (domainObject.DomainMode >= DomainMode.Windows2003Domain)
            {
                Console.WriteLine("PASSED");
            }
            else
            {
                Console.WriteLine("FAILED");
            }

            Console.WriteLine();
        }

        static List<int> TestTcpPorts(List<int> portList)
        {
            Console.WriteLine("Testing TCP ports to {0}:", _ipAddr.ToString());

            List<int> failedPorts = new List<int>();

            foreach (int port in portList)
            {
                Console.Write("Checking TCP port {0}: ", port);

                TcpClient tcpClient = new TcpClient();

                try
                {
                    tcpClient.Connect(_ipAddr, port);

                    tcpClient.Close();
                    Console.WriteLine("PASSED");
                }
                catch (SocketException)
                {
                    failedPorts.Add(port);
                    Console.WriteLine("FAILED");
                }
            }

            Console.WriteLine();

            return failedPorts;
        }

        static List<int> TestUdpPorts(List<int> portList)
        {
            Console.WriteLine("Testing UDP ports to {0}:", _ipAddr.ToString());

            List<int> failedPorts = new List<int>();

            foreach (int port in portList)
            {
                Console.Write("Checking UDP port {0}: ", port);

                UdpClient udpClient = new UdpClient();

                try
                {
                    udpClient.Connect(_ipAddr, port);
                    udpClient.Close();
                    Console.WriteLine("PASSED");
                }
                catch (SocketException)
                {
                    failedPorts.Add(port);
                    Console.WriteLine("FAILED");
                }
            }

            Console.WriteLine();

            return failedPorts;
        }
    }
}

Create an AD Connector

To connect to your existing directory with AD Connector, perform the following steps. Before starting this procedure, make sure you have completed the prerequisites identified in AD Connector prerequisites.

For more information on what is created with your AD Connector, see What gets created with your AD Connector.