Duo Single Sign-On for Zerto

Overview

As business applications move from on-premises to cloud hosted solutions, users experience password fatigue due to disparate logons for different applications. Single sign-on (SSO) technologies seek to unify identities across systems and reduce the number of different credentials a user has to remember or input to gain access to resources.

While SSO is convenient for users, it presents new security challenges. If a user's primary password is compromised, attackers may be able to gain access to multiple resources. In addition, as sensitive information makes its way to cloud-hosted services it is even more important to secure access by implementing two-factor authentication and zero-trust policies.

About Duo Single Sign-On

Duo Single Sign-On is our cloud-hosted SSO product which layers Duo's strong authentication and flexible policy engine on top of Zerto logins. Duo Single Sign-On acts as an identity provider (IdP), authenticating your users using existing on-premises Active Directory (AD) or another SSO IdP. Duo SSO prompts users for two-factor authentication and performs endpoint assessment and verification before permitting access to Zerto.

Duo Single Sign-On is available in Duo Premier, Duo Advantage, and Duo Essentials plans, which also include the ability to define policies that enforce unique controls for each individual SSO application. For example, you can require that Salesforce users complete two-factor authentication at every login, but only once every seven days when accessing Zerto. Duo checks the user, device, and network against an application's policy before allowing access to the application.

Configure Single Sign-On

Before configuring Zerto with Duo SSO using Security Assertion Markup Language (SAML) 2.0 authentication you'll first need to enable Duo Single Sign-On for your Duo account and configure a working authentication source.

Once you have your SSO authentication source working, continue to the next step of creating the Zerto application in Duo.

Create the Zerto Application in Duo

1. Log on to the Duo Admin Panel and navigate to Applications → Protect an Application.

2. Locate the entry for Zerto with a protection type of "2FA with SSO hosted by Duo (Single Sign-On)" in the applications list. Click Protect to the far-right to start configuring Zerto. See Protecting Applications for more information about protecting applications with Duo and additional application options. You'll need the information on the Zerto page under Downloads later.

3. Zerto uses the Mail attribute, First name attribute, and Last name attribute when authenticating. We've mapped the bridge attributes to Duo Single Sign-On supported authentication source attributes as follows:

   Bridge Attribute	Active Directory	SAML IdP
   <Email Address>	mail	Email
   <First Name>	givenName	FirstName
   <Last Name>	sn	LastName

   If you are using non-standard attributes for your authentication source, check the Custom attributes box and enter the names of the attributes you wish to use instead.

4. You can adjust additional settings for your new SAML application at this time — like changing the application's name from the default value, enabling self-service, or assigning a group policy.

5. Keep the Duo Admin Panel tab open. You will come back to it later.

Duo Universal Prompt

The Duo Universal Prompt provides a simplified and accessible Duo login experience for web-based applications, offering a redesigned visual interface with security and usability enhancements.

Universal Prompt	Traditional Prompt

The Duo Zerto application supports the Universal Prompt by default, so there's no additional action required on your part to start using the newest authentication experience.

Activate Universal Prompt

Activation of the Universal Prompt is a per-application change. Activating it for one application does not change the login experience for your other Duo applications. Universal Prompt is already activated for new Zerto applications at creation.

The "Universal Prompt" area of the application details page shows that this application's status is "Activation complete", with these activation control options:

• Show traditional prompt: Your users experience Duo's traditional prompt via redirect when logging in to this application.
• Show new Universal Prompt: (Default) Your users experience the Universal Prompt via redirect when logging in to this application.

The application's Universal Prompt status shows "Activation complete" both here and on the Universal Prompt Update Progress report.

For the time being, you may change this setting to Show traditional prompt to use the legacy experience. Keep in mind that support for the traditional Duo prompt ended for the majority of applications in March 2024. This option will be removed in the future.

Universal Update Progress

Click the See Update Progress link to view the Universal Prompt Update Progress report. This report shows the update availability and migration progress for all your Duo applications. You can also activate the new prompt experience for multiple supported applications from the report page instead of visiting the individual details pages for each application.

Enable Zerto for SSO

1. Log into your Zerto account as an administrator.

2. At the top of the left menu sidebar, click the drop-down menu and select zerto.

3. In the web address bar, make note of your IP address. You will need it later.

   Example: If the web address bar URL is https://192.168.11.123/auth/admin/master, then your IP address is https://192.168.11.123.

4. In the left menu sidebar, click Identity providers. The "Identity providers" page opens.

5. Under "User-defined", click SAML v2.0. The "Add SAML provider" page opens.

6. Enter a unique name for your alias into the Alias field.

7. Enter a unique name for your display into the Display name field.

8. Under "SAML settings", click the Use entity descriptor toggle switch to "Off".

9. Return to the Duo Admin Panel. Under "Downloads", click Download XML.

10. Return to Zerto. Click Browse next to the Import config from file field and open the XML file you downloaded from Duo earlier.

11. Scroll down and click the Want AuthnRequests signed toggle switch to "On".

12. Click the SAML signature key name drop-down menu and select CERT_SUBJECT.

13. Click the Validate Signatures toggle switch to "On".

14. Scroll down to the bottom of the page and click Add. Your provider details page opens.

15. Click the Mappers tab.

16. Click Add mapper. The "Add Identity Provider Mapper" page opens.

17. Type Email Mapper into the Name field.

18. Click the Sync mode override drop-down menu and select Force.

19. Click the Mapper type drop-down menu and select Attribute Importer.

20. Type email into the Friendly Name field.

21. Type email into the User Attribute Name field.

22. Click Save.

23. At the top of the page, click the Provider details link. Your provider details page opens.

24. Click Add mapper. The "Add Identity Provider Mapper" page opens.

25. Type First Name Mapper into the Name field.

26. Click the Sync mode override drop-down menu and select Force.

27. Click the Mapper type drop-down menu and select Attribute Importer.

28. Type firstName into the Friendly Name field.

29. Type firstName into the User Attribute Name field.

30. Click Save.

31. At the top of the page, click the Provider details link. Your provider details page opens.

32. Click Add mapper. The "Add Identity Provider Mapper" page opens.

33. Type Last Name Mapper into the Name field.

34. Click the Sync mode override drop-down menu and select Force.

35. Click the Mapper type drop-down menu and select Attribute Importer.

36. Type lastName into the Friendly Name field.

37. Type lastName into the User Attribute Name field.

38. Click Save.

39. At the top of the page, click the Provider details link. Your provider details page opens.

40. Under "General settings", click the SAML 2.0 Service Provider Metadata link. The XML file opens in a new tab.

41. Right-click within the XML file text and save the file to your computer.

42. Return to the Duo Admin Panel. Under "Service Provider", click Choose File and open the XML file you saved from Zerto earlier.

43. In the Duo Admin Panel, scroll to the bottom of the page and click Save.

Group Mapping

You have the option to map Duo groups to different group attributes in Zerto. To map Duo groups, do the following:

1. Log into your Zerto account as an administrator.

2. At the top of the left menu sidebar, click the drop-down menu and select zerto.

3. In the left menu sidebar, click Identity providers. The "Identity providers" page opens.

4. Click your identity provider. Your provider details page opens.

5. Click the Mappers tab.

6. Click Add mapper. The "Add Identity Provider Mapper" page opens.

7. Type Groups Mapper into the Name field.

8. Click the Sync mode override drop-down menu and select Force.

9. Click the Mapper type drop-down menu and select Advanced Attribute to Group.

10. Type groups into the Key field.

11. Enter a unique name for your group attribute into the Value field.

12. Click Select group. The "Select group" pop-up window opens.

13. Click the desired group and then click Select.

14. Click Save.

15. At the top of the page, click the Provider details link. Your provider details page opens.

16. In the "Name" column, click Groups Mapper. The "Edit Identity Provider Mapper" page opens.

17. Copy the text in the Value field and paste it into the Duo Admin Panel Zerto groups attribute value field.

18. In the Duo Admin Panel, click the Duo groups drop-down menu and select the applicable Duo groups to map.

    

19. Scroll down to the bottom of the page and click Save.

Learn more about Zerto SSO at the Zerto Knowledge Portal.

Using SSO

You can log on to Zerto by navigating to your Zerto SSO page, which is the IP address you noted earlier e.g., https://192.168.11.123. Click your identity provider name to be redirected to Duo Single Sign-On to begin authentication.

Active Directory Login

With Active Directory as the Duo SSO authentication source, enter the primary username (email address) on the Duo SSO login page and click or tap Next.

Enter the AD primary password and click or tap Log in to continue.

Enable Duo Passwordless to log in to Duo SSO backed by Active Directory authentication without entering a password in the future.

SAML Login

With another SAML identity provider as the Duo SSO authentication source, Duo SSO immediately redirects the login attempt to that SAML IdP for primary authentication. Users do not see the Duo SSO primary login screen.

Duo Authentication

Successful verification of your primary credentials by Active Directory or a SAML IdP redirects back to Duo. Complete Duo two-factor authentication when prompted and then you'll return to Zerto to complete the login process.

* Universal Prompt experience shown.

Zerto supports SP-initiated authentication only, meaning that you must start your SSO login from that application's sign-in page. You won't be able to add Zerto as an application tile in Duo Central for IdP-initiated logins.

Congratulations! Your Zerto users now authenticate using Duo Single Sign-On.

See the full user login experience, including expired password reset (available for Active Directory authentication sources) in the Duo End User Guide for SSO.

Enable Remembered Devices

To minimize additional Duo two-factor prompts when switching between Zerto and your other Duo Single Sign-On SAML applications, be sure to apply a shared "Remembered Devices" policy to your SAML applications.

Troubleshooting

Need some help? Try searching our Knowledge Base articles or Community discussions. For further assistance, contact Support.