Step 7.2. Create conditional access root certificates for VPN authentication with Azure AD

Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2, Windows 10

In this step, you configure conditional access root certificates for VPN authentication with Azure AD, which automatically creates a Cloud app called VPN Server in the tenant. To configure conditional access for VPN connectivity, you need to:

  1. Create a VPN certificate in the Azure portal.
  2. Download the VPN certificate.
  3. Deploy the certificate to your VPN and NPS servers.

Important

Once a VPN certificate is created in the Azure portal, Azure AD will start using it immediately to issue short lived certificates to the VPN client. It is critical that the VPN certificate be deployed immediately to the VPN server to avoid any issues with credential validation of the VPN client.

When a user attempts a VPN connection, the VPN client makes a call into the Web Account Manager (WAM) on the Windows 10 client. WAM makes a call to the VPN Server cloud app. When the Conditions and Controls in the Conditional Access policy are satisfied, Azure AD issues a token in the form of a short-lived (1-hour) certificate to the WAM. The WAM places the certificate in the user's certificate store and passes off control to the VPN client. 

The VPN client then sends the certificate issued by Azure AD to the VPN for credential validation. 

Note

Azure AD uses the most recently created certificate in the VPN connectivity blade as the Issuer.

Procedure:

  1. Sign in to your Azure portal as a global administrator.
  2. On the left menu, click Azure Active Directory.
  3. On the Azure Active Directory page, in the Manage section, click Security.
  4. On the Security page, in the Protect section, click Conditional Access.
  5. On the Conditional Access | Policies page, in the Manage section, click VPN Connectivity.
  6. On the VPN connectivity page, click New certificate.
  7. On the New page, perform the following steps: a. For Select duration, select either 1, 2 or 3 years. b. Select Create.

Next steps

Step 7.3. Configure the Conditional Access policy: In this step, you configure the conditional access policy for VPN connectivity.