Learn how to synchronize Duo users and groups from your existing OpenLDAP directory.
Import Duo user names and other identity information directly from your on-premises OpenLDAP directory into Duo with Duo Security's Directory Sync feature.
Duo Directory Sync is a one-way operation. No information from Duo is imported into your user directory. Synchronization runs on a daily schedule, or on-demand when initiated from the Admin Panel or programmatically via Admin API.
The Directory Sync feature is part of the Duo Beyond, Duo Access, and Duo MFA plans.
Before executing any OpenLDAP synchronization with Duo, understand the effect that synchronization can have on accounts with the same name. Suppose that you already have some Duo users, and one or more of these users have the same username on your OpenLDAP server. Performing a synchronization will cause the existing Duo users' information to be merged with, and in some cases overwritten by the OpenLDAP information, such as email addresses in Duo changing to match the value stored in the synced directory.
Likewise, if you synchronize multiple directories and there are non-unique usernames among those directories, the net result is that there will be only one Duo user created with that username, and each sync will update that Duo user with different information.
Multiple syncs with different source directories that use non-unique user names may also produce undesired results, as each sync process could overwrite the user with different information.
Prerequisites necessary for OpenLDAP synchronization are as follows:
cnattribute, used as the Duo group name after import.
entrydn(used as the distinguished name) and
entryuuid(the group unique identifier).
memberOfattribute (via the memberOf overlay).
Verify that your OpenLDAP directory satisfies all the class and attribute requirements before attempting the sync. LDAP variants other than OpenLDAP may require additional configuration or modules to provide the necessary attributes to Duo.
Role required: Owner, Administrator, or User Manager.
To start setting up Directory Sync:
To start setting up Directory Sync:
Log in to the Duo Admin Panel and click Users in the left side bar. Then click Directory Sync on the submenu or click the Directory Sync link on the "Users" page.
Click the OpenLDAP tab heading, and then click the Add New OpenLDAP Sync button.
You'll be taken to the details page for your new directory sync in the Duo Admin Panel. The new directory's name defaults to OpenLDAP Sync (and increments for each additional directory added i.e. "OenLDAP Sync (2)"). Click the Rename link if you'd like to change the directory sync's name to something different, clicking Save to apply the new name.
The "Status" section of the page shows you the current state of your directory sync. When your OpenLDAP sync setup is complete, you'll be able to verify the connection here.
As you have just created the new directory, the status indicates your next step is to deploy and configure the Duo Authentication Proxy.
The next step after saving the directory settings is to install the Duo Authentication Proxy software on a machine that can connect to both Duo's cloud service and to your LDAP server. Before proceeding, you should locate (or set up) a system in your environment on which you will install the Duo Authentication Proxy. This host needs LDAP connectivity to your LDAP server (ports 389/636 or whichever ports accept LDAP binds), as well as HTTPS/443 connectivity to Duo.
If you are already running an Authentication Proxy server in your environment, you can also use that host for directory synchronization.
The minimum recommended Authentication Proxy version for OpenLDAP synchronization is 2.6.0, but we always recommend installing or updating to the latest version.
This application communicates with Duo's service on TCP port 443. Firewall configurations that restrict outbound access to Duo's service with rules using destination IP addresses or IP address ranges aren't recommended, since these may change over time to maintain our service's high availability. If your organization requires IP-based rules, please review this Duo KB article.
Locate (or set up) a system on which you will install the Duo Authentication Proxy. The proxy supports Windows and Linux systems (in particular, we recommend Windows Server 2012 R2 or later, Red Hat Enterprise Linux 6 or later, CentOS 6 or later, or Debian 6 or later).
The Duo Authentication Proxy can be installed on a physical or virtual host. We recommend a system with at least 1 CPU, 200 MB disk space, and 4 GB RAM (although 1 GB RAM is usually sufficient).
Ensure that Perl and a compiler toolchain are installed. On most recent RPM-based distributions — like Fedora, RedHat Enterprise, and CentOS — you can install these by running (as root):
$ yum install gcc make libffi-devel perl zlib-devel
On Debian-derived systems, install these dependencies by running (as root):
$ apt-get install build-essential libffi-dev perl zlib1g-dev
Download the most recent Authentication Proxy for Unix from https://dl.duosecurity.com/duoauthproxy-latest-src.tgz. Depending on your download method, the actual filename may reflect the version e.g. duoauthproxy-5.0.2-src.tgz. View checksums for Duo downloads here.
Extract the Authentication Proxy files and build it as follows:
$ tar xzf duoauthproxy-latest-src.tgz $ cd duoauthproxy-version-src $ make
Install the authentication proxy (as root):
$ cd duoauthproxy-build $ ./install
Follow the prompts to complete the installation. The installer creates a user to run the proxy service and a group to own the log directory and files. You can accept the default user and group names or enter your own.
If you ever need to uninstall the proxy, run
After the installation completes, you will need to configure the proxy. Note that as of v4.0.0, the default file access for the
conf directory is restricted to the built-in "Administrators" group during installation on Windows systems.
The Duo Authentication Proxy configuration file is named
authproxy.cfg, and located in the
conf subdirectory of the proxy installation.
|Windows||v5.0.0 and later||
|Windows||v4.0.2 and earlier||
Download the Authentication Proxy
authproxy.cfg file for your OpenLDAP sync by clicking the Duo Authentication Proxy Config link in step 2 of the Duo Authentication Proxy section of the directory properties page.
The configuration file is formatted as a simple INI file. Section headings appear as:
Individual properties beneath a section appear as:
A first time Authentication Proxy install may include an existing
authproxy.cfg with some example content. If this is the first time you're configuring this Authentication Proxy server, you should delete the existing sample content and paste in the information from the
authproxy.cfg file download from the directory properties page.
authproxy.cfg file for OpenLDAP sync contains a
[cloud] section with the following properties:
NTLMv1, NTLMv2, or Plain authentication
|ikey||Your integration key.|
|skey||Your secret key.|
|api_host||Your API hostname (i.e.,
|service_account_username||The account used to bind to OpenLDAP. This account needs read-only access to your directory.|
|service_account_password||The directory password for the service_account_username user.|
Add the information from your downloaded
authproxy.cfg to your Authentication Proxy server configuration file. Make sure to save your configuration file when done.
To configure an existing Authentication Proxy server for directory sync, simply append the
[cloud] section of the config file downloaded from the Duo Admin Panel directory properties page to the current
authproxy.cfg file located in the Duo Security Authentication Proxy conf folder. Save the configuration file then restart the Duo Authentication Proxy service. Note that there can only be one
[cloud] section in the
Here's a sample
authproxy.cfg file for Plain authentication:
[cloud] ikey=DIXXXXXXXXXXXXXXXXXX skey=2v3O7uCJmdhFK6hsKS82HGyNUR5L1XGCRx44DjCQ api_host=api-XXXXXXXX.duosecurity.com service_account_username=duosync service_account_password=Pass12345
When running the Authentication Proxy on Windows, you may encrypt the directory user password for NTLMv1/v2/Plain authentication stored in the
[cloud] section if you do not want to store them as plain text. Use the
authproxy_passwd.exe program, which can be found in the
bin directory of your Authentication Proxy installation.
c:\>"C:\Program Files\Duo Security Authentication Proxy\bin\authproxy_passwd.exe" Password: Re-enter password: AQAAANCMnd8BFdERjHoAwE/Cl+sBAAAA5hII/4JlnEeB5xMBzB5D/wQAAAAeAAAAdwBpAG4AMwAyAGMAcgB5AHAAd ABvAC4AcAB5AAAAA2YAAMAAAAAQAAAA5AHAAdABvAC4AcAB5AAAAA2YAAMAAAAAQAAAASApm6tif+wDKj+Rt0UtQ9 QAAAAAEgAlnEeB5xMBzB5D/wQAAAAeAAAAdwBpAG4AMwAyAGMAcgB5AHAAdABvQ8M7voQmwOOxqv91QmJs9QAAAAA EgAAAoAAAABAAAACxWVslLxrlFOunUUeq+kg1CAAAAPFj+oygch2RFAAAAD9HgbRonCsy/GNx4M9FxSq/KJCq
Copy and paste the output into your configuration file as and remove any line breaks. You may find it easier to redirect the command output to a file and then open the file in Notepad.
The encrypted password is specific to the server where it was generated, and will not work if copied to a different machine. If you have multiple Authentication Proxy servers with the same service account specified, be sure to run
authproxy_passwd.exe separately on each one.
Here's a sample
authproxy.cfg file for Plain authentication with an encrypted password:
[cloud] ikey=DIXXXXXXXXXXXXXXXXXX skey=2v3O7uCJmdhFK6hsKS82HGyNUR5L1XGCRx44DjCQ api_host=api-XXXXXXXX.duosecurity.com service_account_username=duosync service_account_password_protected=QAAANCMnd8BFdERjHoAwE/Cl+sBAAAA5hII/4JlnEeB5xMBzB5D/wQAAAAeAAAAdwBpAG4AMwAyAGMAcgB5AHAAdABvAC4AcAB5AAAAA2YAAMAAAAAQAAAA5AHAAdABvAC4AcAB5AAAAA2YAAMAAAAAQAAAASApm6tif+wDKj+Rt0UtQ9QAAAAAEgAlnEeB5xMBzB5D/wQAAAAeAAAAdwBpAG4AMwAyAGMAcgB5AHAAdABvQ8M7voQmwOOxqv91QmJs9QAAAAAEgAAAoAAAABAAAACxWVslLxrlFOunUUeq+kg1CAAAAPFj+oygch2RFAAAAD9HgbRonCsy/GNx4M9FxSq/KJCq
To start the Duo Authentication Proxy service on Windows, launch an Administrator command prompt and run:
net start duoauthproxy
Or, open the "Services" console (services.msc), locate the "Duo Security Authentication Proxy Service" in the list of services and click on it to select, and then click the start button.
To start the Duo Authentication Proxy on Linux, run:
Once you've started the Authentication Proxy service, return to the directory sync configuration page and click the Test Connection link in step 4 of the Authentication Proxy section. The directory status will indicate the proxy is connected and you're ready to move on to the next setup step, Directory Configuration. If you don't see the proxy connected, double-check the information in your authproxy.cfg and make sure the proxy service is running, then test the connection again.
Enter the required directory connection information:
Enter the IP address or hostname of your OpenLDAP directory server, followed by the port the Authentication Proxy server should use to contact the directory server.
The typical port for unsecured LDAP or STARTTLS is 389, and LDAPS is usually 636.
Click Add Directory Server to add additional hosts. If the first server in the list doesn't respond when performing a sync, the next server is used as a fallback. If you decommission any of your directory servers be sure to return to Duo and remove it from the list.
The base DN should be a level in your directory structure above both the users and groups you plan to synchronize.
Select the type of authentication the Authentication Proxy will use to connect to your LDAP server. One of:
The transport type selected determines how the connection between the Duo Authentication Proxy software and the LDAP server is encrypted, if at all. Connectivity between the Duo Authentication Proxy software and the Duo Security cloud services is always HTTPS secured with SSL and is not affected by this setting. One of:
Selecting LDAPS or STARTTLS exposes additional settings:
Click Save Directory after entering the Directory Configuration information. If the Duo Authentication Proxy was able to contact the specified directory server and perform a search for groups using the given Base DN, then the status shown in the Directory Sync section will show as Connected.
Continue configuring the directory sync by updating the Synced Attributes.
No default source attributes are defined for OpenLDAP sync. You'll need to specify the source attributes from your LDAP directory for these Duo user properties:
Required. The source attribute for the Duo username. The attribute selected should match the primary authentication login name your users submit to Duo. This attribute cannot be customized after the first directory synchronization occurs.
Specify up to eight directory attributes to import as additional usernames for each Duo user by clicking Add a username alias attribute, choosing which alias number to define, and entering the desired source attribute from your directory.
For example, if the Username source attribute is
Be sure to choose directory attributes that have unique values (email address, employee ID, etc.). If any of the username or username alias attribute values is the same for two or more users, those users will be skipped by the sync process.
Unlike the Username, the attributes used for username aliases may be changed after the first directory synchronization.
Default: No aliases imported. Aliases may be defined manually from the Admin Panel or programmatically via Admin API on a per-user basis.
Required. The user's name.
Required. The user's email address. This is used as the destination address for enrollment emails from Duo.
Enable this option if you want Directory Sync to import notes information for your users.
Populate the "Notes" field for a Duo user with information from the specified OpenLDAP directoryy attribute.
Only configurable if Import notes is selected.
Enable this option if you want Directory Sync to create phones for your users. Imported devices default to the "Generic Smartphone" platform.
If you enable both the Enrollment email and Import phones options, enrollment links are only sent to users with email addresses who do not have phone information populated in the directory.
Default: Import no phone information from OpenLDAP.
Required. Create a phone in Duo with the attribute value as the phone number, attached to the imported user as a generic smartphone 2FA device. Non-US numbers must be stored in the directory using the format
To import a landline with an extension, append
Only configurable if Import phones is selected.
Create a phone in Duo with the attribute value as the phone number, attached to the imported user as an additional generic smartphone 2FA device. Non-US numbers must be stored in the directory using the format
To import a landline with an extension, append
Only configurable if Import phones is selected.
Click the Save Directory button and proceed to group selection.
Click in the Selected Groups box and start typing an OpenLDAP group name; the list of available groups to sync returned will match the filter. If you have a very large number of groups in your directory, Duo limits the search results to 100 groups, so you may need to type in most of your desired sync group's name or DN (like CN=Duo-Users,OU=Groups,DC=domain,DC=local) to locate it.
If you don't see any of your LDAP groups listed, review the previous setup steps and correct your configuration.
Once you see your intended group (or a list of groups), click to select the desired group or groups to sync, then click Save Directory once you've added all the groups you want to import. You can select up to 400 groups to sync from the source directory. Members of the groups you choose here will be synced into Duo.
Nested groups are supported; Duo sync imports users from groups nested within your sync group, but creates only the top level group in Duo (the group explicitly selected for directory sync), with all nested group members as direct members of that Duo group.
If you delete and recreate any of the LDAP groups saved in the sync properties (even if you reused the same group name and members), then you'll need to return to the directory sync property page for your OpenLDAP directory on the Duo Admin Panel and delete the recreated group from your sync configuration, then re-add the group, and save the directory.
Select the Enrollment Email option if you want imported users to automatically receive an enrollment link email when the sync process completes. Only users imported with active status, a valid email address, and who do not already have any enrolled authentication devices in Duo receive an emailed link. The email address is populated by OpenLDAP sync.
Default: Do not send enrollment emails to imported users.
The enrollment link sent when the sync first imports a user is valid for 30 days. Duo sends an emailed enrollment reminder if the user hasn't yet completed enrollment after two days, and then a second reminder if the user remains unenrolled eight days after the first reminder.
If the user does not complete the enrollment process after 30 days has elapsed, the original enrollment link expires and a new enrollment link is generated at the next sync and sent to the user. This entire 30 day cycle repeats until the user completes Duo enrollment.
The contents of the enrollment email subject and body can be changed on the global Settings page. The enrollment email body should contain the placeholder text "<enrollment-link>", which will be replaced by the link to the enrollment form when the email is sent. The sent message will have a non-editable header added, informing the user it's an automated message sent by Duo and to contact their organization's Duo admins or IT support group with any questions.
If your organization uses e-mail filtering, be sure to allow the sender email@example.com.
Click Save Directory to complete the new OpenLDAP setup in Duo.
Duo Beyond and Duo Access Plan Users: Global Policy settings affect access to the enrollment portal. Do not apply any global restrictions that could prevent user enrollment. For example, if you configure the User Location policy setting to deny access to a country, then the policy will also block any of your users who attempt to enroll in Duo from that country via a bulk enrollment link. The New User Policy setting for the enrollment portal is always "Require Enrollment".
The directory page shows the status as Connected once all directory configuration steps have been completed successfully. You'll also see options to Sync directory and Sync individual users.
Click Sync Directory Now to run your first sync and immediately import all members of your selected OpenLDAP groups into Duo.
When complete, you'll see a count of users and groups synced into Duo.
Whether you run your first sync immediately after setup or not, directory sync runs automatically once a day (at a set time chosen at random). You can always return to the Duo Admin Panel to initiate a manual sync.
Note that once you import users from OpenLDAP into Duo you may not change the username source attribute, but you can enable or disable username normalization. See the FAQ for more information.
Role required: Owner, Administrator, User Manager, or Help Desk.
When you just need to import information for a few users from OpenLDAP you can interactively sync selected users instead of syncing the entire directory. For example, you may have some new employee accounts in your LDAP directory who need a corresponding Duo account, or you might have just changed some attribute value for an OpenLDAP user and need that information carried over to Duo. Syncing these individual user accounts updates Duo immediately.
To sync individual users:
Navigate to the directory's details page in the Duo Admin Panel.
Type up to 50 OpenLDAP user names as a comma-separated list into the Sync individual users text box found in the "Directory Sync" section on the directory's properties page. You must type each username exactly as it is shown (or will be shown) in Duo i.e. if you opted to use
Additionally, individually synced users must be members of a group specified as a "Selected Group" in your directory's configuration. If you try to sync an individual user who is not a member of a selected group then no update of that user occurs.
Click the Sync Users button to import information about the specified user or users.
When initiated, the individual user sync verifies that that each specified user is a member of a group currently synced with Duo and then imports information for that user into Duo. If a specified user doesn't already exist in Duo, the sync creates them using the information imported from the source directory. If you enabled the option to send enrollment emails and the new user has the email address attribute populated, then a new user created by the individual user sync receives an emailed enrollment link.
Individual user sync updates an existing specified user with information from the source directory. The sync can change attribute values (except the username) and modify group memberships.
If you include a specified user that is no longer a member of any group synced into Duo, then the sync marks the user for deletion.
In addition to syncing individual users by username from the directory's details page, you can also perform an individual sync on an existing Duo user by visiting that user's properties page in the Duo Admin Panel and clicking the Sync This User link at the top-right.
Use the AdminAPI directory key from the "Directory Sync" section of the page to perform a sync operation on an individual user using Duo's Admin API.
After adding new users to Duo through OpenLDAP synchronization, your next step is to have them activate their Duo access (if you chose not to send enrollment emails to synced users when creating your directory in Duo). Because a phone created by directory sync defaults to the "Generic Smartphone" platform, on the Users page you'll see a notification bar indicating that users have not yet activated the Duo Mobile smartphone app. This bar provides a link to click to send these users activation links.
For more information on user activation, see Activating Duo Mobile After Enrollment.
If you did choose to send enrollment emails to synced users automatically, the Pending Enrollments table shows which users created by directory sync (or bulk enrollment) have not yet completed enrolling their 2FA devices in Duo, along with the user's email address and the expiration date for the enrollment link previously sent. If you need to send the user another copy of the enrollment link email, click the Resend button. Resending the email does not change the current enrollment link's expiration date.
User attributes synced from an external directory cannot be edited in Duo via the Admin Panel, Admin API, or CSV import. This always applies to the required attributes username, full name, email address, plus phone numbers (if you chose to import phones), and group memberships. Changes to these user attributes should be made in the external directory and then synced over to Duo.
You may edit Duo user properties that aren't synced from OpenLDAP via the Admin Panel, Admin API, or CSV import, including those that correspond with optional OpenLDAP sync attributes you chose not to import. However, if you update your OpenLDAP sync to begin importing values for a previously unconfigured optional attribute, the sync will overwrite any previously configured values with the information imported from OpenLDAP.
You do not enable import of or specify a source attribute for Notes when you create your OpenLDAP directory sync. The sync imports the username, email, and name from OpenLDAP, but imports no notes information. You can edit the "Notes" field for synced Duo users. but you may not edit the "Username", "Full Name", or "Email" properties for synced users.
You specify a source attribute for Username alias 1 but not for aliases 2-4. The sync imports values for "Username Alias 1" from OpenLDAP, and no other aliases. You can't edit "Username Alias 1" for a synced user, but you can edit the values for aliases 2-4.
You do not specify a source attribute for Username alias 1. The sync creates users with no aliases, and you manually add values for "Username Alias 1" to some Duo users from the Admin Panel. You update your configured OpenLDAP sync to add a source attribute for Username alias 1. The next sync updates the "Username Alias 1" value for all synced users to match the value in LDAP, overwriting the aliases you added manually.
Admins can't disable individual Duo users managed by directory sync from the Duo Admin Panel, Admin API, or CSV import. Directory sync disables users removed from the selected synced groups and puts those users in the Trash "Pending Deletion" when a full sync runs. A single-user sync disables users removed from the sync groups (and the next full sync moves the users into the Trash).
You can restore the disabled Duo account to active status by adding the account back to the synced group in the source directory and running a sync.
You may disable a group of synced users by changing the status of that group to Disabled. This prevents any user who is a member of that group from logging in with Duo, regardless of that individual user's status. See the Using Groups and Group Status Administration documentation for more information.
You may not delete a synced user from Duo as long as directory sync is actively managing that user. If a synced directory user is removed from all external directory groups that sync to Duo (or if the user account is deleted from the source directory), the user is sent to the Trash and marked as "Pending Deletion", and the user can no longer authenticate to Duo. The user's properties are read-only and you are no longer billed for that user.
Locate users pending deletion in the Trash view, accessed by clicking the Trash count shown at the top of the Users page.
If the user marked for deletion is not reconnected to an external directory account via the sync within seven days the user is automatically deleted from Duo. The user's properties show the target date for deletion. A Duo admin can manually delete a synced user from the Trash via the Permanently Delete link at any time during those seven days.
Duo groups created by directory sync may only be managed by the sync. You can't change the group's members interactively from the Admin Panel interface, via CSV import, or programmatically with the Admin API.
To update the members of a sync-managed group, make the necessary changes in the source directory and import them into Duo by running a full or single-user sync.
Groups managed by OpenLDAP sync are identified as such in the Admin Panel and Admin API output. When viewing groups in the Admin Panel, you'll see from OpenLDAP Sync "name of sync" appended to the group's name or as the group's description. In Admin API output the sync information is appended to the group's name.
You can have multiple syncs managing groups with the same name (such as a "Duo Users" group managed by AD sync and also a "Duo Users" group managed by Azure sync), or even a manually created "Duo Users" group not managed by any sync. Each sync-managed group only contains Duo user members managed by the same directory sync, and an unmanaged group can only contain users also not managed by any directory sync.
Removing a group from the directory's configuration in Duo marks any members of that group for deletion if they are not members of another synchronized group, and converts the group to unmanaged so it can be modified or deleted from the Duo Admin Panel or Admin API. Duo updates the group's name to indicate it was once managed by directory sync, changing from _Group name_ from OpenLDAP Sync "name of sync" to _Group name_ (formerly from "name of sync").
Deleting a directory from Duo doesn't delete or disable any of the previously imported objects. When you delete a synced directory from Duo, then the users, phones, and groups formerly managed by that sync remain available and get converted to unmanaged Duo objects that can be manually updated or deleted.
Users previously synced remain available and retain the status previously assigned, whether applied to the synced group or to the individual user. Any authentication devices associated with the user remain available. The users retain their former group memberships.
Groups previously synced remain available and retain the same members and status assigned when they were managed by the sync. The group name changes from _Group name_ from type of sync "name of sync" to _Group name_ (formerly from "name of sync").
Phones previously synced remain in Duo attached to the same users. Activation status remains unchanged.
To delete a synced directory:
In the Duo Admin Panel, navigate to Users → Directory Sync and click the OpenLDAP Directory tab.
Click on the directory you want to delete to view its configuration page.
Click the Delete Directory link at the top-right and confirm that you want to delete that directory.
Be sure to review frequently asked questions and answers before using Duo's OpenLDAP synchronization.
Need some help? Take a look at the OpenLDAP Sync Frequently Asked Questions (FAQ) page or try searching our OpenLDAP Sync Knowledge Base articles or Community discussions. For further assistance, contact Support.
On the details page of your directory sync there is a Troubleshooting section under the “Sync Directory Now” button. Here you'll find tips to help your sync run as intended. If you are still having issues and need to open a support case with Duo, you can click Sync Full Directory with Diagnostics to provide Duo Support with more information about your sync.
Additionally, a sync reference code is now provided on every sync. This will be included on every directory sync event captured in the Administrator Actions Log, as well as within any emails Duo sends you about sync errors. Duo Support will request this code to locate logs associated with your sync.