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Configure access for Active Directory manually

Getting started with Teleport Desktop Access for Windows Servers

Getting started with Teleport Desktop Access for Windows Servers

Length: 24:47

This guide demonstrates how to connect an Active Directory domain and how to log into a Windows desktop from the connected domain.

You should note that Teleport requires the Kerberos authentication protocol to support certificate-based authentication for Active Directory. Because Azure Active Directory doesn't use Kerberos, you can't use the Teleport Windows Desktop Service for Azure Active Directory.

Prerequisites

To complete the steps in this guide, verify your environment meets the following requirements:

  • Access to a running Teleport cluster, tctl admin tool, and tsh client tool version >= 16.4.2.

    You can verify the tools you have installed by running the following commands:

    tctl version

    Teleport Enterprise v16.4.2 go1.22


    tsh version

    Teleport v16.4.2 go1.22

    You can download these tools by following the appropriate Installation instructions for the Teleport edition you use.

  • A Linux server to run the Teleport Windows Desktop Service. You can use an existing server that runs the Teleport agent for other resources.

  • An Active Directory domain that is configured for LDAPS. Because Teleport requires an encrypted LDAP connection, you should verify that your domain uses Active Directory Certificate Services or a non-Microsoft certification authority (CA) to issue LDAPS certificates.

  • Administrative access to a domain controller.

  • To check that you can connect to your Teleport cluster, sign in with tsh login, then verify that you can run tctl commands using your current credentials.

    For example:

    tsh login --proxy=teleport.example.com --user=[email protected]
    tctl status

    Cluster teleport.example.com

    Version 16.4.2

    CA pin sha256:abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678

    If you can connect to the cluster and run the tctl status command, you can use your current credentials to run subsequent tctl commands from your workstation. If you host your own Teleport cluster, you can also run tctl commands on the computer that hosts the Teleport Auth Service for full permissions.

Option 1: Automated configuration

For relatively simple Active Directory environments, you can use the tctl generated configuration script to bootstrap your Active Directory domain for use with Teleport. At a high level, the script does the following:

  1. Create a restrictive service account named Teleport Service Account with the SAM account name svc-teleport and create the necessary LDAP containers.
  2. Prevent the service account from performing interactive logins by creating and linking a Group Policy Object (GPO) named Block teleport-svc Interactive Login.
  3. Configure a GPO named Teleport Access Policy to allow Teleport connections, including:
    • Importing the Teleport CA certificate.
    • Configuring firewall rules.
    • Allowing remote RDP connections.
    • Enabling RemoteFX for improved remote desktop performance.
  4. Read the LDAP CA certificate (required for secure LDAPS connections).
  5. Generate a Teleport configuration file for the Windows Desktop Service.

For more complex Active Directory environments, you may need to modify the generated script to meet your specific requirements. It may also be easier to comprehend what the script does by following the manual configuration steps below.

To use the tctl generated configuration script, run the following command:

# Generate the script and save it to a file named configure-ad.ps1.
tctl desktop bootstrap > configure-ad.ps1

After generating the script, transfer it to a Windows domain controller and run it in a PowerShell console.

Option 2: Manual configuration

Step 1/7. Create a restrictive service account

Teleport requires a service account to connect to your Active Directory domain. You should create a dedicated service account with restrictive permissions for maximum security.

To create the service account:

  1. Open PowerShell on a Windows domain computer.

  2. Create a service account with a randomly-generated password by copying and pasting the following script into the PowerShell console:

    $Name="Teleport Service Account"
    $SamAccountName="svc-teleport"
    
    # Generate a random password that meets the "Password must meet complexity
    # requirements" security policy setting.
    # Note: if the minimum complexity requirements have been changed from the
    # Windows default, this part of the script may need to be modified.
    Add-Type -AssemblyName 'System.Web'
    do {
       $Password=[System.Web.Security.Membership]::GeneratePassword(15,1)
    } until ($Password -match '\d')
    $SecureStringPassword=ConvertTo-SecureString $Password -AsPlainText -Force
    
    New-ADUser `
      -Name $Name `
      -SamAccountName $SamAccountName `
      -AccountPassword $SecureStringPassword `
      -Enabled $true
    

    The password generated for the service account is discarded immediately. Teleport doesn't need the password because it uses x509 certificates for LDAP authentication. You can reset the password for the service account if you need to perform password authentication.

  3. Set the minimum permissions that must granted to the service account by running the following script in the PowerShell console:

    # Save your domain's distinguished name to a variable.
    $DomainDN=$((Get-ADDomain).DistinguishedName)
    
    # Create the CDP/Teleport container.
    # If the command fails with "New-ADObject : An attempt was made to add an object
    # to the directory with a name that is already in use", it means the object
    # already exists and you can move on to the next step.
    New-ADObject -Name "Teleport" -Type "container" -Path "CN=CDP,CN=Public Key Services,CN=Services,CN=Configuration,$DomainDN"
    
    # Allow Teleport to create LDAP containers in the CDP container.
    dsacls "CN=CDP,CN=Public Key Services,CN=Services,CN=Configuration,$DomainDN" /I:T /G "$($SamAccountName):CC;container;"
    
    # Allow Teleport to create and delete cRLDistributionPoint objects in the CDP/Teleport container.
    dsacls "CN=Teleport,CN=CDP,CN=Public Key Services,CN=Services,CN=Configuration,$DomainDN" /I:T /G "$($SamAccountName):CCDC;cRLDistributionPoint;"
    
    # Allow Teleport to write the certificateRevocationList property in the CDP/Teleport container.
    dsacls "CN=Teleport,CN=CDP,CN=Public Key Services,CN=Services,CN=Configuration,$DomainDN " /I:T /G "$($SamAccountName):WP;certificateRevocationList;"
    
    # Allow Teleport to read the cACertificate property in the NTAuthCertificates container.
    dsacls "CN=NTAuthCertificates,CN=Public Key Services,CN=Services,CN=Configuration,$DomainDN" /I:T /G "$($SamAccountName):RP;cACertificate;"
    
  4. Get the security identifier for the new service account. For example, run the following command:

    Get-AdUser -Identity $SamAccountName | Select SID
    

    The command returns the security identifier for the specified account:

    SID
    ---
    S-1-5-21-209875886-835680547-4265310078-1113
    
  5. Copy the full security identifier—beginning with S-—returned.

    You'll use this value for the sid field when you configure the ldap settings in a later step.

Step 2/7. Prevent the service account from performing interactive logins

The next steps modify group policy objects (GPOs). Changes to group policies can take time to propagate to all hosts. You can force changes to take effect immediately on your current host by opening PowerShell and running gpupdate.exe /force. However, the change might still take time to propagate to other hosts in the domain.

The Teleport service account is only needed to authenticate over LDAP. The account doesn't need to log on to Windows computers like an ordinary user. You can prevent the service account from being used to log on by creating a new Group Policy Object (GPO) linked to your entire domain, and then denying interactive logins.

Create a GPO

  1. Open PowerShell and specify a name for the new group policy object with the $GPOName variable:

    $GPOName="Block teleport-svc Interactive Login"
    
  2. Create the new GPO by running the following command in the PowerShell console:

    New-GPO -Name $GPOName | New-GPLink -Target $((Get-ADDomain).DistinguishedName)
    

Deny interactive login

  1. Open Group Policy Management and expand Forest > Domains > $YOUR_DOMAIN > Group Policy Objects to locate the group policy object you just created.

  2. Select the group policy object, click Action, then select Edit.

  3. Expand Computer Configuration > Policies > Windows Settings > Security Settings > Local Policies > User Rights Assignment.

  4. Double-click Deny log on locally, then select Define these policy settings.

  5. Click Add User or Group, then click Browse.

  6. Type all or part of the service account name—for example, svc-teleport—then click Check Names.

  7. Verify the Teleport Service Account is selected, then click OK in all the dialogs.

    Deny Interactive Login
  8. Repeat these steps for Deny log on through Remote Desktop Services.

For added security, you can disable username and password authentication completely. If you disable username and password authentication, only the Teleport virtual smart card can be used to access Windows computers in the domain.

Step 3/7. Configure a GPO to allow Teleport connections

To enable access to Windows desktop sessions through Teleport, you must configure a group policy object that allows Windows computers to trust the Teleport certificate authority and accept certificate-based smart card authentication.

You need to do the following to configure the group policy object:

  • Export a certificate signed by the Teleport certificate authority for an existing Teleport cluster.
  • Create a new group policy object and import the signed Teleport certificate.
  • Publish the signed Teleport certificate to the Active Directory domain.
  • Publish the signed Teleport certificate to the NTAuth Store.
  • Enable smart card authentication.
  • Allow remote desktop connections.

You must repeat these steps if you rotate the Teleport user certificate authority.

Export the Teleport certificate

To export the Teleport user CA certificate:

  1. Log on to a Windows domain controller where you can access Group Policy Management.

  2. Open PowerShell and download the Teleport user certificate authority by running the following command and replacing teleport.example.com with the address of your Teleport cluster:

    curl.exe -fo user-ca.cer https://teleport.example.com/webapi/auth/export?type=windows
  3. Take note of the path to the user-ca.cer file for use in a later step.

Create the GPO for the Teleport certificate

To configure the group policy object:

  1. Create a new group policy object with the name Teleport Access Policy by running the following command:

    $GPOName="Teleport Access Policy"
    New-GPO -Name $GPOName | New-GPLink -Target $((Get-ADDomain).DistinguishedName)
    

    This command applies the GPO to the entire Active Director domain. If you only want to protect a subset of computers in the domain, you can apply the GPO to a specific organizational unit (OU) that only includes those computers.

    If you use AWS Managed Microsoft Active Directory, AWS Delegated Domain Administrator accounts are not granted permissions to apply GPOs at the domain level. Instead, you should apply this GPO to the automatically-created OU with the NetBIOS domain name containing Computers and Users nested one level inside the domain root.

    AWS Managed AD OU Location
  2. Open Group Policy Management and expand Forest, Domains, your domain, and Group Policy Objects to locate the GPO you just created.

  3. Select the new GPO—for example, Teleport Access Policy, right-click, then select Edit.

  4. In the group policy editor, expand Computer Configuration > Policies > Windows Settings > Security Settings > Public Key Policies.

  5. Right-click Trusted Root Certification Authorities, then click Import.

  6. Use the wizard to select and import the Teleport certificate.

    Import Teleport CA
  7. To ensure your GPO update takes effect immediately on this host, open PowerShell and run the following command (optional):

    gpupdate.exe /force
    

Publish the Teleport CA to the Active Directory domain

To publish the Teleport certificate in the Active Directory domain:

  1. Log on to a Windows computer that is joined to the Active Directory domain with an account that's a member of the Domain Administrators or AWS Delegated Domain Administrators group.

  2. Open PowerShell and run the following command using the path to the user-ca.cer file you exported from Teleport:

    certutil -dspublish -f user-ca.cer RootCA
    

    This command enables the domain controllers to trust the Teleport CA so that certificate-based smart card authentication through Teleport can succeed.

Publish the Teleport CA to the NTAuth Store

For authentication with Teleport-issued certificates to succeed, the Teleport CA also must be published to the enterprise NTAuth store. Teleport periodically publishes its CA after it is able to authenticate, but this step must be performed manually the first time for Teleport to have LDAP access.

To publish the Teleport CA to LDAP:

  1. Open PowerShell and run the following command using the path to the user-ca.cer file:

    certutil -dspublish -f user-ca.cer NTAuthCA
    
  2. Force the retrieval of the CA from LDAP by running the following command:

    certutil -pulse
    

    This step isn't strictly required. However, it allows you to proceed to the next steps without waiting for the certificate to propagate.

Enable smart card authentication

Teleport performs certificate-based authentication by emulating a smart card.

To add smart card authentication to your group policy object:

  1. Verify that you have the Teleport Access Policy group policy object open in the group policy editor.

  2. Expand Computer Configuration > Policies > Windows Settings > Security Settings > System Services.

  3. Double-click Smart Card and select Define this policy setting.

  4. Select Automatic, then click OK.

    Enable the Smart Card Service
  5. To ensure your GPO update takes effect immediately on this host, open PowerShell and run the following command (optional):

    gpupdate.exe /force
    

Allow remote desktop connections

Next you need to configure policies that allow remote connections to domain computers.

  1. Verify that you have the Teleport Access Policy group policy object open in the group policy editor.

  2. Expand Computer Configuration > Policies > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Connections.

  3. Right-click Allow users to connect remotely by using Remote Desktop Services, select Edit, select Enabled, then click OK.

  4. Under Remote Desktop Session Host, select Security.

  5. Right-click Require user authentication for remote connections by using Network Level Authentication, select Edit, select Disabled, then click OK.

    NLA Support

    Teleport 16.2.0 and later support NLA. If you are running a supported version and enable NLA, you can skip this step. Read more in the NLA section.

    Disable Require user authentication...
  6. Right-click Always prompt for password upon connection, select Edit, select Disabled, then click OK.

    The Teleport certificate-based smart card authentication generates a random smart card PIN for each desktop session and provides the PIN to the desktop when establishing the RDP connection. Because the PIN is never provided to the Teleport user, the Always prompt for password upon connection policy must be disabled for authentication to succeed.

  7. Expand Computer Configuration, Policies, Windows Settings, Security Settings to select Windows Firewall with Advanced Security.

  8. Right-click Inbound Rules, select New Rule.

    • Under Predefined, select Remote Desktop, then click Next.
    • Select User Mode (TCP-in), then click Next.
    • Select Allow the connection, then click Finish.
    Open the Firewall
  9. To ensure your GPO update takes effect immediately on this host, open PowerShell and run the following command (optional):

    gpupdate.exe /force
    

Enable RemoteFX

To finish configuring the Teleport Access Policy group policy object, you must enable RemoteFX. RemoteFX is a compression technology that significantly improves the performance of remote desktop connections.

  1. Verify that you have the Teleport Access Policy group policy object open in the group policy editor.

  2. Expand Computer Configuration > Policies > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Remote Session Environment > RemoteFX for Windows Server 2008 R2

  3. Right-click Configure RemoteFX, select Edit, select Enabled, then click OK.

    Enable RemoteFX (Step 1)
  4. Now left-click Remote Session Environment (Computer Configuration > Policies > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Remote Session Environment in the left pane) and from the items in the right pane, right-click Enable RemoteFX encoding for RemoteFX clients designed for Windows Server 2008 R2 SP1, select Edit, select Enabled, then click OK.

    Enable RemoteFX (Step 2)
  5. Again left-click Remote Session Environment in the left pane, and from the items in the right pane, right-click Limit maximum color depth, select Edit, select Enabled, then click OK.

    Enable RemoteFX (Step 3)
  6. Open PowerShell and run the following command to update your Teleport group policy object:

    gpupdate.exe /force
    

Step 4/7. Configure a certificate for RDP connections

The Teleport RDP client requires secure cryptographic algorithms to make TLS connections. However, Windows Server 2012 R2 doesn't support these algorithms by default.

You can configure Windows Server 2012 R2 to support the required algorithms by doing the following:

  • Create a new certificate template that uses elliptic curve cryptography.
  • Update the Teleport group policy object to use the new certificate template when issuing certificates for remote desktop connections.

If your hosts support the required algorithms, you can skip this step and go to Export your LDAP CA certificate.

Create a certificate template

To create a certificate template that uses elliptic curve P-384 and SHA384 as the signature algorithm:

  1. Click Start, Control Panel, and Administrative Tools to select Certificate Authority.

  2. Open your CA computer, right-click Certificate Templates, then select Manage.

  3. Select the Computer template, right-click, then select Duplicate Template.

  4. Select the Compatibility tab:

    • Change Certification Authority to Windows Server 2012 R2, then click OK.
    • Change Certificate recipient to Windows Server 2012 R2, then click OK.
  5. Select the General tab:

    • Change Template display name to RemoteDesktopAccess.
    • Verify that Template name is also RemoteDesktopAccess.
  6. Select the Cryptography tab:

    • Change Provider Category to Key Storage Provider.
    • Change Algorithm name to ECDH_P384.
    • Change Request hash to SHA384.
  7. Select the Extensions tab:

    • Select Application Polices, then click Edit.
    • Remove all entries from the list.
  8. Select the Security tab:

    • Select Domain Computers and give the group Read and Enroll permissions.
  9. Click OK to create the Template.

  10. Go back to the Certificate Authority console, right-click Certificate Templates.

  11. Click New, select Certificate Template to Issue, then select RemoteDesktopAccess.

  12. Click OK.

Update GPO to use a new certificate template

To update the Teleport group policy object to use the new certificate template:

  1. Open the Teleport Access Policy group policy object in the group policy editor.

  2. Expand Computer Configuration > Policies > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Security.

  3. Right-click Server authentication certificate template, select Edit, select Enabled, then set the Certificate Template Name to RemoteDesktopAccess.

    RDP Certificate Template
  4. Expand Computer Configuration, Policies, and Windows Settings to select Public Key Policies.

  5. Double-click Certificate Services Client - Auto-Enrollment, then select Enabled in the Configuration Model.

  6. Open PowerShell and run the following command to update your Teleport group policy object:

    gpupdate.exe /force
    

Step 5/7. Export your LDAP CA certificate

Teleport connects to your domain controller using LDAPS. This means that you must let Teleport know that the certificate sent by your domain controller during the initial connection is trusted. If your domain controller's certificate is trusted by the system repository on the system running Teleport, you can skip this step.

If you are unable to acquire the LDAP CA certificate, you can skip TLS verification by setting insecure_skip_verify: true. However, you shouldn't skip TLS verification in production environments.

To export a CA certificate:

  1. Click Start, Control Panel, and Administrative Tools to select Certificate Authority.
  2. Select your CA computer, right-click, then select Properties.
  3. One the General tab, click View Certificate.
  4. Select Details, then click Copy to File.
  5. Click Next in the Certificate Export Wizard, and ensure that DER encoded binary X.509 (.CER) is selected.
  6. Select a name and location for the certificate and click through the wizard.
  7. Transfer the exported file to the system where you're running Teleport. You can either add this certificate to your system's trusted repository or provide the file path to the der_ca_file configuration variable.

Step 6/7. Configure Teleport

To configure Teleport to protect access to Windows desktops:

  1. Install Teleport on the Linux host that will run the Teleport Windows Desktop Service:

    Install Teleport on your Linux server:

    1. Assign edition to one of the following, depending on your Teleport edition:

      EditionValue
      Teleport Enterprise Cloudcloud
      Teleport Enterprise (Self-Hosted)enterprise
      Teleport Community Editionoss
    2. Get the version of Teleport to install. If you have automatic agent updates enabled in your cluster, query the latest Teleport version that is compatible with the updater:

      TELEPORT_DOMAIN=example.teleport.com
      TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/automaticupgrades/channel/default/version | sed 's/v//')"

      Otherwise, get the version of your Teleport cluster:

      TELEPORT_DOMAIN=example.teleport.com
      TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/ping | jq -r '.server_version')"
    3. Install Teleport on your Linux server:

      curl https://cdn.teleport.dev/install-v16.4.2.sh | bash -s ${TELEPORT_VERSION} edition

      The installation script detects the package manager on your Linux server and uses it to install Teleport binaries. To customize your installation, learn about the Teleport package repositories in the installation guide.

  2. Sign in to your Teleport cluster from your administrative workstation.

  3. Generate an invitation token for the cluster with the following command:

    tctl tokens add --type=windowsdesktop
  4. Copy the invitation token to a file on the Linux host that will run the Windows Desktop Service.

  5. Add the configuration for the Windows Desktop Service to the /etc/teleport.yaml on the Linux host.

    The /etc/teleport.yaml should include configuration settings similar to the following:

    version: v3
    teleport:
      auth_token: path-to-token
      proxy_server: teleport.example.com # replace with your proxy address
    windows_desktop_service:
      enabled: yes
      ldap:
        # Port must be included for the addr.
        # LDAPS port is 636 by default (example.com:636)
        addr: "$LDAP_SERVER_ADDRESS"
        domain: "$LDAP_DOMAIN_NAME"
        username: "$LDAP_USERNAME"
        sid: "$LDAP_USER_SID"
        # Path to the certificate you exported.
        der_ca_file: path-to-exported-cert
      discovery:
        base_dn: "*"
    auth_service:
      enabled: no
    proxy_service:
      enabled: no
    ssh_service:
      enabled: no
    

    For a detailed description of the configuration fields, see Desktop Configuration Reference.

  6. Configure the Teleport Desktop Service to start automatically when the host boots up by creating a systemd service for it. The instructions depend on how you installed the Teleport Desktop Service.

    On the host where you will run the Teleport Desktop Service, enable and start Teleport:

    sudo systemctl enable teleport
    sudo systemctl start teleport

    On the host where you will run the Teleport Desktop Service, create a systemd service configuration for Teleport, enable the Teleport service, and start Teleport:

    sudo teleport install systemd -o /etc/systemd/system/teleport.service
    sudo systemctl enable teleport
    sudo systemctl start teleport

    You can check the status of the Teleport Desktop Service with systemctl status teleport and view its logs with journalctl -fu teleport.

Step 7/7. Log in using Teleport

Teleport users must have appropriate permissions to access remote Windows desktops. For example, you can create a role that gives its users access to all Windows desktop labels and the local "Administrator" user.

To create a role for accessing Windows desktops:

  1. Create a file called windows-desktop-admins.yaml with the following content:

    kind: role
    version: v5
    metadata:
      name: windows-desktop-admins
    spec:
      allow:
        windows_desktop_labels:
          "*": "*"
        windows_desktop_logins: ["jsmith"]
    

    Note that user names shared between domain and local users create login conflicts.

  2. Create the role:

    tctl create -f windows-desktop-admins.yaml
  3. Assign the windows-desktop-admins role to your Teleport user by running the appropriate commands for your authentication provider:

    1. Retrieve your local user's roles as a comma-separated list:

      ROLES=$(tsh status -f json | jq -r '.active.roles | join(",")')
    2. Edit your local user to add the new role:

      tctl users update $(tsh status -f json | jq -r '.active.username') \ --set-roles "${ROLES?},windows-desktop-admins"
    3. Sign out of the Teleport cluster and sign in again to assume the new role.

    1. Open your github authentication connector in a text editor:

      tctl edit github/github
    2. Edit the github connector, adding windows-desktop-admins to the teams_to_roles section.

      The team you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the team must include your user account and should be the smallest team possible within your organization.

      Here is an example:

        teams_to_roles:
          - organization: octocats
            team: admins
            roles:
              - access
      +       - windows-desktop-admins
      
    3. Apply your changes by saving closing the file in your editor.

    4. Sign out of the Teleport cluster and sign in again to assume the new role.

    1. Retrieve your saml configuration resource:

      tctl get --with-secrets saml/mysaml > saml.yaml

      Note that the --with-secrets flag adds the value of spec.signing_key_pair.private_key to the saml.yaml file. Because this key contains a sensitive value, you should remove the saml.yaml file immediately after updating the resource.

    2. Edit saml.yaml, adding windows-desktop-admins to the attributes_to_roles section.

      The attribute you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the group must include your user account and should be the smallest group possible within your organization.

      Here is an example:

        attributes_to_roles:
          - name: "groups"
            value: "my-group"
            roles:
              - access
      +       - windows-desktop-admins
      
    3. Apply your changes:

      tctl create -f saml.yaml
    4. Sign out of the Teleport cluster and sign in again to assume the new role.

    1. Retrieve your oidc configuration resource:

      tctl get oidc/myoidc --with-secrets > oidc.yaml

      Note that the --with-secrets flag adds the value of spec.signing_key_pair.private_key to the oidc.yaml file. Because this key contains a sensitive value, you should remove the oidc.yaml file immediately after updating the resource.

    2. Edit oidc.yaml, adding windows-desktop-admins to the claims_to_roles section.

      The claim you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the group must include your user account and should be the smallest group possible within your organization.

      Here is an example:

        claims_to_roles:
          - name: "groups"
            value: "my-group"
            roles:
              - access
      +       - windows-desktop-admins
      
    3. Apply your changes:

      tctl create -f oidc.yaml
    4. Sign out of the Teleport cluster and sign in again to assume the new role.

    Now that you have a Linux host running the Windows Desktop Service and a role that allows Teleport users to connect to Windows computers, you can use the Teleport user assigned the windows-desktop-admins role to connect to Windows desktops from the Teleport Web UI.

To connect to a Windows desktop:

  1. Sign in to the Teleport cluster using an account that's assigned the windows-desktop-admins role.

  2. Select Resources.

  3. Click Type, then select Desktops.

  4. Click Connect for the Windows computer you want to access, then select the login to use for the connection.

    Teleport opens a remote desktop connection and starts recording the desktop session. When you're finished working with the Windows desktop, click the More items menu, then click Disconnect.

    To view the recording, select Management in the Teleport Web UI, then click Session Recordings in the Activity section.

Security hardening

By default, the Default Domain Policy grants the Add workstations to domain user right to all authenticated users. As a security best practice, Teleport recommends that you only grant this right to administrators or other privileged groups.

To change the default domain policy:

  1. Open Group Policy Management and expand Forest, Domains, your domain, and Group Policy Objects.
  2. Right-click Default Domain Controller Policy, then select Edit.
  3. In the group policy editor, expand Computer Configuration, Policies, Windows Settings, Security Settings, Local Policies, and User Rights Assignment to select Add workstations to domain.
  4. Double-click the Add workstations to domain policy and ensure that the Authenticated Users group is not present.

Multiple domains

Each windows_desktop_service is designed to support connecting to hosts in a single Active Directory domain. If you have multiple independent domains, you can deploy multiple Teleport agents to service them.

If you have multiple domains with a trust relationship between them, you can configure Teleport to perform PKI operations against one domain, while generating certificates for users in another domain.

In order for this to work, the hosts that you want to connect to and the AD users that you want to connect as must reside in the same domain.

For example, suppose you have a root domain at example.com and a child domain for developers at dev.example.com. If your PKI is configured at the root, but you want to allow users in the child domain to connect to hosts in the child domain, you would do the following:

  1. Import Teleport's CA certificate as a trusted root certificate in the root domain's group policy and add the certificate to the NTAuth store as described in the section above.
  2. Configure Teleport to perform PKI against the root domain, while issuing certificates for users and hosts in the child domain:
windows_desktop_service:
  enabled: yes

  # configure LDAP settings to point at the child domain
  ldap:
    addr: dev.example.com:636
    username: 'DEV\svc-teleport'

  # optional: configure discovery for the child domain
  discovery:
    base_dn: CN=Computers,DC=dev,DC=example,DC=com

  # perform PKI against the root domain
  pki_domain: root.example.com

With this configuration, Teleport will generate certificates for users in dev.example.com, but it will publish its CA and CRLs to example.com.

Network Level Authentication (NLA)

With Teleport 16.2.0 and later, you can configure windows_desktop_service to perform Network Level Authentication (NLA) when connecting to Windows hosts. NLA is a security feature that authenticates the user prior to establishing the remote desktop connection, which ensures that the remote Windows host doesn't consume system resources to present a login screen to an unauthenticated user.

In order to perform NLA, Teleport's windows_desktop_service needs to be able to make an outbound Kerberos connection to a key distribution center (KDC). This is most commonly performed on TCP port 88.

By default, Teleport will assume that a KDC is available on the same host that is specified in the ldap configuration's addr field, using the default Kerberos port.

For example, with the following configuration, Teleport will attempt to perform NLA against example.com:88.

windows_desktop_service:
    enabled: yes
    ldap:
      addr: example.com:636

Alternatively, you can override the KDC address by specifying the kdc_address in your Teleport configuration file.

windows_desktop_service:
    enabled: yes
    kdc_address: kdc.example.com   # defaults to port 88 if unspecified

To enable NLA, set the TELEPORT_ENABLE_RDP_NLA environment variable to yes on any hosts running the Teleport's windows_desktop_service. Note that NLA is only supported when connecting to hosts that are part of an Active Directory domain. Teleport will not perform NLA when connecting to hosts as a local Windows user.

Computer Name

In order to complete a successful authentication flow, Teleport needs to know the hostname of the target Windows server. If you are using Teleport's LDAP-based discovery no action is necessary - Teleport will default to using the teleport.dev/computer_name label which is automatically populated. If this label is not present then Teleport will use the desktop's addr field.

If you register your Windows hosts via configuration file or via Teleport's API and you want to enable NLA, then you should either:

  • manually set the teleport.dev/computer_name label to the proper hostname
  • ensure that the host's addr is its actual hostname

Next steps

If you encounter any issues, see Troubleshooting for common problems and solutions. For information about configuring Windows-specific role permissions, see Role-Based Access Control for Desktops.