Introduction
Integrating VMware vCenter Server with Active Directory (AD) enables centralized user management and simplifies access administration. Instead of relying on vCenter’s local user database, you can use your AD domain or another LDAP service as a single source of authentication.
This means that vSphere administrators can use the same accounts and groups they use for other network resources to access vSphere objects. This approach enhances security by centralizing credential control and simplifies access management (e.g., adding a user to the appropriate domain group automatically grants them the necessary permissions in vCenter). Additionally, domain-based authentication allows you to use AD security mechanisms such as password policies, multi-factor authentication via federation, etc., to access vCenter.
This article provides a step-by-step guide for integrating vCenter Server 8.0/8.1 with Active Directory and LDAP, as well as the best practices for 2025 – including recommendations for security, high availability, and centralized administration. We’ll begin with system preparation and then cover the two main integration methods:
- Joining vCenter to the AD domain (Integrated Windows Authentication – a legacy method);
- Adding LDAP as an identity source (recommended method).
Next, we’ll explain how to assign roles to AD users in vCenter and offer tips for optimal configuration. Finally, we’ll summarize the key takeaways.
Prerequisites and Requirements
Before starting integration, ensure the following prerequisites are met:
- A configured Active Directory domain must be available – there should be at least one domain controller (not in read-only mode). For high availability, it’s recommended to have multiple domain controllers.
- Proper DNS configuration – the vCenter name or Fully Qualified Domain Name (FQDN) must match the domain, and vCenter must correctly resolve the DNS names of AD domain controllers. Please ensure that the vCenter Server Appliance (VCSA) is pointing to a DNS server capable of resolving the AD domain name to a domain controller’s IP address.
- Time synchronization – vCenter and the domain controller(s) must have synchronized time (e.g., using NTP). A time drift greater than 5 minutes may cause Kerberos authentication failures.
- An AD account with appropriate privileges – required to either join computers to the domain (if using the domain-join method) or perform LDAP queries (if using the LDAP method). It’s recommended to create a dedicated account (e.g., vmware_svc) with the minimum necessary domain permissions.
- SSO vCenter domain name uniqueness – the local vCenter Single Sign-On (SSO) domain (default: vsphere.local) must not conflict with your AD domain name. For example, if your corporate domain is company.local, the vCenter SSO domain should use a different name (e.g., vsphere.local) to avoid integration issues.
See configuration details in Image 1.

Image 1
Integration Methods with Active Directory
There are two main methods to integrate vCenter with Active Directory:
- Joining vCenter Server to a Windows domain (Integrated Windows Authentication, IWA) – a traditional method where vCenter becomes a member of the AD domain. This includes Kerberos trust and enables the use of Windows Session Authentication (single sign-on for the account logged into Windows) for the vSphere Web Client.
Important: VMware has announced the deprecation of this method – support for IWA will be removed in upcoming major versions after vSphere 8.0. Therefore, although this method is still available in vCenter 8.0/8.1, a transition to alternative methods is recommended.
- Adding AD as an LDAP identity source (LDAP/LDAPS) – this is the recommended approach for 2025. With this method, vCenter does not join the domain. Instead, an external identity source is added in the SSO settings, pointing to the Active Directory domain via the LDAP/LDAPS protocol. It is preferable to use the secure LDAPS channel (LDAP over SSL) to encrypt authentication traffic. This method requires uploading the domain controller’s certificate for LDAPS manually and does not support single sign-on via the Windows session. However, it is more secure and better supported in the long term.
Below you can find step-by-step instructions for each approach.
Method 1: Joining vCenter 8.x to an Active Directory domain (IWA)
Note: This method is now considered deprecated; however, it is still supported in vCenter versions 8.0/8.1 for backward compatibility. Its use may be justified if you require login via the current Windows session (SSPI) or if your process explicitly depends on domain join integration. However, plan to migrate to the LDAP-based method (see below) in the near future.
1. Log in to the vSphere Client Using an SSO Account
Open the vCenter Web UI (vSphere Client) and log in using the SSO administrator account – typically administrator@vsphere.local (or another account specified during vCenter setup). This account has full rights to configure SSO. Make sure you have access to the administrative interface of vCenter.
2. Open Single Sign-On Settings
In the vSphere Client, click the Menu button (square icon at the top) and go to the Administration section. Under Single Sign-On, select Configuration. Switch to the Identity Provider tab.
See configuration details in Image 2.

Image 2
3. Join the Domain
In the Identity Provider tab, find the Active Directory Domain section and click Join AD to start the process of joining the vCenter Server Appliance to the domain. The following dialog box (See Image 3) will appear where you can enter domain parameters:

Image 3
4. Enter Domain Parameters
In the dialog window that appears, enter the credentials required to join the domain:
- Domain – the fully qualified domain name (FQDN) of the Active Directory domain, e.g., corp.local. Keep in mind that this name must be different from the vCenter SSO domain.
- Organizational Unit (OU) – this field is optional. You can specify the DN of the OU where the vCenter computer object should be placed in AD. If left blank, the object will go to the default “Computers” container. For example, the value OU=Servers,DC=corp,DC=local will place the record in the OU “Servers” of the corp.local domain.
- Username and Password – a domain account with permissions to add computers. Use the login format user@domain or DOMAIN\user. It is recommended to use a dedicated account (e.g., vmwareadmin) that is a member of the Domain Admins group, rather than the built-in Administrator.
After filling in the fields, click Join to submit the request. If successful, the operation will join the VCSA to the AD domain and prompt for a reboot of the vCenter Server.
5. Reboot vCenter
Restart the vCenter Appliance to apply the changes (a restart is often required when configuring domain services). After the reboot, vCenter will be a member of the specified domain (a corresponding computer account will appear in AD).
6. Add the Domain as an Identity Source
Log in to the vSphere Client again using the SSO administrator account (administrator@vsphere.local). Go to Administration > Single Sign-On > Configuration > Identity Provider, and open the Identity Sources tab. You should see a source of the Active Directory (Integrated Windows Authentication) type for the domain you joined. If not, click Add and manually choose the Active Directory (Integrated Windows Authentication) type. Typically, joining the domain causes vCenter to automatically register this domain as an SSO identity source. If this did not occur, add it manually: select your domain from the dropdown or enter its name and NetBIOS alias, then save. Once added, the domain will appear as a new entry of Active Directory type in the Identity Sources list (see Image 4).

Image 4
7. Set the Default Domain (Optional)
If your environment is only going to use one external identity source (your AD domain), it makes sense to set it as the Default Domain – the default source for authentication. To do this, highlight the added domain in the Identity Sources list and click Set as Default. In the Type column next to the domain, you’ll see the label “(default)”. Now, when entering a username without explicitly specifying the domain (e.g., just john.dow instead of CORP\john.dow), vCenter will attempt to authenticate it against your AD domain.
8. Verify Login via Windows Session (SSPI)
The key benefit of joining the domain is the ability to log into vCenter using your current Windows session, without re-entering a password. To verify this, use Internet Explorer/Edge or the vSphere Client launched from a machine that is part of the same domain, and select the Use Windows session authentication option on the vSphere Client login page. Alternatively, enter user@domain in the username field and leave the password blank with Windows Session enabled (See Image 5). If everything is configured correctly, you’ll be automatically authenticated using your domain credentials (SSO will pass the Kerberos ticket).
Important: This mechanism only works with the IWA method and when the browser/client supports SPNEGO authentication, and when you are logged into the AD domain on the client machine with the same user.

Image 5
Method 2: Adding Active Directory via LDAP/LDAPS (Recommended)
Integrating vCenter with AD via LDAP does not require the vCenter Server to be joined to the domain. vCenter will send LDAP requests to the AD controller(s) to validate credentials. As of 2025, VMware recommends this method because it avoids using the outdated IWA method and supports secure LDAPS connections. Below are the steps to configure an LDAP identity source:
1. Prepare an LDAPS Certificate
If you plan to use secure LDAP (LDAPS, port 636), prepare an SSL certificate for your domain controller in advance. Typically, domain controllers have a certificate (issued by an internal enterprise CA or self-signed) for LDAP over SSL. This certificate (or the CA certificate that issued it) must be imported into vCenter during identity source configuration.
Note: The vCenter’s web UI doesn’t offer an automatic way to retrieve a certificate from the LDAP server, so you’ll need to do this manually. You can either:
- Export the domain controller certificate from the Windows certificate store (if accessible), or
- Run the OpenSSL command on the vCenter Appliance:
openssl s_client -showcerts -connect dc01.corp.local:636
This command outputs the certificate chain. Copy the content of the
—–BEGIN CERTIFICATE—– … END CERTIFICATE—– block for the root or issuing CA and save it to a file (e.g. ldaps.cer).
It’s recommended to use the domain CA certificate so that when the domain controller’s certificate is updated, you don’t have to reconfigure the identity source.
- If secure LDAP is unavailable, you can temporarily use plain LDAP (port 389), though this is not recommended for security reasons.
2. Add a New Identity Source
Log in to the vSphere Client as the SSO administrator (administrator@vsphere.local) and navigate to Administration > Single Sign-On > Configuration. On the Identity Provider tab, open the Identity Sources section and click Add. In the identity source wizard, choose Identity Source Type = Active Directory over LDAP (see Image 6).
If you’re integrating a non-Microsoft LDAP service (e.g., OpenLDAP), choose the corresponding OpenLDAP type instead. The fields are similar, although Domain name and Alias are only applicable to AD.

Image 6
3. Fill in LDAP Parameters
Enter the following configuration details for the new identity source (see Image 7):

Image 7
- Identity source name – a friendly name for the identity source in vCenter. Usually, the domain DNS name is used, e.g., corp.local.
- Base Distinguished Name for users – the base DN for user lookups. To cover the entire domain, use the root DN. For example, for corp.local, this would be DC=corp,DC=local.You can also specify a narrower context (e.g., a specific OU) if you only want users from a particular department.
- Base Distinguished Name for groups – the base DN for group lookups. You can use the same root DN or a specific OU if groups are stored separately.
- Domain name – the full domain name, e.g., corp.local.
- Domain alias (NetBIOS name) – the short domain name (NetBIOS), e.g., CORP. This is used for logins in the DOMAIN\user format. This field is not available for OpenLDAP sources.
- Username and Password – credentials for connecting to LDAP. Provide a domain user with read access to the directory. Basic browse permissions are sufficient – any standard AD user will do, since Authenticated Users can view the directory structure by default.
It is recommended to use a dedicated service account with limited rights.
Use either the UPN format (user@corp.local) or the DN format (e.g., CN=vmware_svc,CN=Users,DC=corp,DC=local). If you receive a DN syntax error while saving, try using the DN format for the username.
- Connect to – this sets the domain controller addresses. You can choose: “Connect to any domain controller in the domain” – vCenter will discover DCs automatically via DNS. This increases availability (vCenter will fall back to another DC if one becomes unavailable). Alternatively, you can specify domain controllers manually – select the “Specific domain controllers” option and provide one or two URLs.
URL formats:
- for LDAPS: ldaps://dc01.corp.local:636 (if required, you may also use port 3269 for the global catalog with SSL).
- for LDAP without SSL: ldap://dc01.corp.local:389 (use port 3268 for the global catalog without SSL).
If specifying two domain controllers, the first will be treated as primary and the second as a fallback if the primary is unavailable.
4. Import the SSL Certificate
If you chose to use LDAPS and your domain controller uses a self-signed or corporate (enterprise) certificate, click Browse next to the Certificate field and upload the certificate file obtained in Step 1 (See Image 8). vCenter will import it into the trusted store to establish an SSL connection with LDAPS.
Make sure the uploaded certificate is correct; otherwise, the connection will fail.

Image 8
5. Complete Identity Source Addition
Click Add to save the configuration. The new identity source will appear in the Identity Sources list. vCenter SSO now recognizes your AD domain and can authenticate its users. If needed, set this identity source as the default domain (click Set as Default) as described in the previous section to simplify login input.
6. Verify the Connection
After adding the identity source, it’s recommended to perform basic checks:
- Go to the Users and Groups tab in the Single Sign-On settings (under Administration). Try switching the domain (in the dropdown list) to the newly added AD domain – you should see a list of AD users or groups, confirming a successful connection.
- If the LDAP connection fails, double-check the Base DN and credentials, and ensure that the LDAPS certificate is valid. In case of authentication errors, review the vCenter SSO logs at /var/log/vmware/sso on the vCenter Appliance.
Note on Other LDAP Services: integration with OpenLDAP or other third-party LDAP services follows the same general steps. Select OpenLDAP as the identity source type and specify the Base DN for users/groups according to your directory structure. If using LDAPS, a certificate will also be required. The main difference is that Domain Name and Alias fields are not needed (these are specific to Active Directory). After adding an OpenLDAP source, you can create SSO groups that include external LDAP users and assign roles to them, or assign permissions to individual LDAP users in a similar way.
Assigning Permissions to AD Users in vCenter
After connecting vCenter to an external identity source (whether AD via IWA or LDAP), domain users still don’t automatically have access to the vSphere infrastructure. You must explicitly assign them roles and permissions in vCenter. Best practice: assign privileges to AD groups instead of individual users – this simplifies administration, allowing user management at the AD level.
Let’s walk through the process of granting a group of virtual infrastructure administrators full access in vCenter:
1. Create an AD Group
Create a group in Active Directory, for example, vCenter-Admin, and add the appropriate domain administrator users to it (if the group doesn’t already exist).
This is done on the domain controller via the Active Directory Users and Computers console (see Image 9).

Image 9
2. Assign the Group Global Permissions in vCenter
In the vSphere Client, go to Administration > Access Control > Global Permissions. Global permissions apply to all vCenter objects (including all datacenters and clusters). Click Add. In the Add Principal window:
- Select your domain (if not selected by default).
- Start typing the group name (e.g., “vCenter-Admin”) in the search field.
Once the group is found, select it (it may take some time for AD groups to appear).
- In the Role dropdown, choose Administrator (or another role depending on the required privileges).
- Make sure the Propagate to children checkbox is selected if you’re assigning permissions at the top level.
- Click OK to apply (See Image 10).
Now, all users in the vCenter-Admin group will inherit Administrator rights to all vCenter objects.

Image 10
3. Verify Authorization with a Domain Account
Open a new vSphere Client session (or log out from the current one) and on the login page, enter the credentials of the AD user who was added to the group with assigned permissions – for example, john.dow@corp.local and their password. If the domain has been set as “default” in SSO, you can enter just the username without the @domain.
Make sure the login is successful and that you can see vCenter environment objects. The name of the logged-in domain user will be shown in the top right corner of the interface. This user now has the permissions granted by the assigned role.
Repeat the process for other users or groups by assigning appropriate roles (e.g., a read-only role for an operators group, or a VM Power User role for developers at the folder level, etc.).
4. Minimize the Use of the Local Administrator Account
Once domain authentication is set up, avoid using the administrator@vsphere.local account for daily operations. Instead, treat it as a break-glass account to be used only in emergencies when AD integration is unavailable. This account must always have a strong password and be securely stored, but it should not be used for routine tasks. All regular operations should be performed using personal domain logins – this improves auditing and aligns with security policies.
Best Practices 2025: Security, Resilience, and Management
1. Use LDAPS and Abandon Unencrypted LDAP
Since 2020, Microsoft has tightened LDAP security requirements – it is recommended to use LDAP Signing or fully switch to LDAPS. Always use LDAPS when integrating vCenter with an external directory. Without encryption, your credentials may be transmitted in plaintext. Moreover, vCenter with IWA previously used unsigned LDAP, which triggers warnings (Event ID 2889) on AD controllers and may be blocked by security policies. By using AD over LDAPS or federation, you avoid this issue. Make sure your domain has a certificate service set up for AD controllers and that vCenter trusts these certificates. If necessary, renew LDAP certificates on your controllers before they expire and import the new ones into vCenter – otherwise, authentication will break when a certificate becomes invalid.
2. Plan for Deprecation of IWA
VMware has announced that Integrated Windows Authentication (IWA) will be removed in future versions (post-8.0 Update 3). It’s recommended to migrate now from domain-join setups to AD over LDAPS or consider implementing federation via a third-party identity provider. Federation (e.g., ADFS, Okta, Azure AD, etc.) allows for modern authentication methods, including MFA, but requires additional configuration. If federation isn’t planned yet, switching to LDAP(S) integration is essential for long-term operations. VMware provides guidelines and tools for migrating from IWA to LDAPS and verifying configuration before upgrading. Bottom line: For new deployments, use LDAP; for existing IWA setups, migrate to LDAP before upgrading vCenter to a version where IWA is no longer supported.
3. Least Privilege and Role-Based Access
Follow the principle of least privilege. While it’s convenient to give Domain Admins full access to vCenter, it’s better to create separate AD groups for specific vCenter roles (e.g., vSphereAdmins, vSphereReadOnly, BackupOperators, etc.). Assign only the roles that a group actually needs – this prevents privilege sprawl. Avoid adding built-in groups like Domain Admins directly to vCenter – use dedicated vSphere-related AD groups for better control over access.
Also, avoid creating local users in the vCenter SSO domain (vsphere.local) unless absolutely necessary. All administration should be done using domain accounts, except in emergencies. Local users should only be created for integrations with external systems (e.g., a service account for a backup solution that doesn’t support domain authentication).
4. Centralized Management and Auditing
By using Active Directory for vCenter, you gain centralized control over user accounts – disabling or deleting a user in AD will automatically revoke their access to vCenter (provided the user doesn’t have other accounts). Take advantage of this and manage access using standard AD tools. In vCenter, regularly review the Administration > Roles and Permissions section to check which groups have which roles. When an employee leaves, simply remove them from the AD group – their vCenter access will be revoked immediately. Also, note that all user operations in vCenter are logged (Events, Tasks) under their domain names, which simplifies action auditing.
5. Ensuring Authentication Resilience
Plan for a backup scenario in case AD or LDAP becomes unavailable. Keep the SSO administrator credentials (and/or another local account with admin rights) readily available to access vCenter if the external directory integration fails. Regularly verify that the password for administrator@vsphere.local is known to a limited group of personnel and securely stored.
Additionally, if vCenter manages critical infrastructure, deploy at least two domain controllers (AD recommends a minimum of two per domain). By default, vCenter uses DNS to locate controllers when configuring LDAP, so if one fails, it will fall back to another. If you specify static controllers, define both primary and secondary. AD redundancy is crucial: losing the sole controller will block domain users from logging into vCenter. In disaster recovery scenarios (e.g., multiple node failures), it’s also beneficial to have offline backups of both AD controllers and the VCSA itself.
6. vCenter and AD Security
When running vCenter in a domain environment, ensure that both vCenter and Active Directory are regularly updated and patched. Restrict network access to services: LDAP/LDAPS ports on domain controllers should only be open to trusted hosts (including vCenter). The vCenter Appliance itself should be protected by a firewall, with management access limited to admins only. Consider enabling two-factor authentication (2FA) for the vCenter Web Client using VMware Identity Manager (Workspace ONE Access) or built-in support for RSA SecurID/SmartCard, if your policy mandates MFA – vCenter SSO supports configuring these methods in addition to AD.
By following these recommendations, you’ll build a secure, reliable, and easy-to-manage access control system for your VMware infrastructure that meets modern security standards and is ready for future updates.
Conclusion
Integrating VMware vCenter Server with Active Directory or another LDAP directory is a crucial step for organizations aiming to centralize account management and enhance security. We reviewed two integration methods for vCenter 8.0 and 8.1: joining a Windows domain (the legacy IWA method) and configuring an LDAP(S) identity source (the modern and recommended method). The provided step-by-step instructions guide you through configuring vCenter-AD integration and assigning the necessary privileges to domain groups and users.
Current best practices encourage administrators to use secure LDAP (LDAPS), phase out deprecated methods, ensure fault tolerance (with domain controller redundancy and backups), and reduce reliance on local accounts in favor of domain accounts. Perform regular permission audits and promptly remove or revoke access when team members change – AD integration significantly simplifies this. Centralized authentication reduces administrative overhead and strengthens the security of your virtual infrastructure, allowing you to focus on its growth rather than manual account management.
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