Zimbra Single Sign-On using SAML with SimpleSAMLphp
Did you know that Zimbra support SAML single sign on? SAML is an open standard that allows you to have a single login page for all applications in your organization. SAML is a Zimbra Network Edition feature. Once you have set-up your SAML portal you can easily add Multi Factor Authentication.
Set up Zimbra SP in SimpleSAMLphp
See the following links that are updated regularly:
Google Workspaces: https://github.com/Zimbra/google-workspaces-saml
Cisco Duo: https://github.com/Zimbra/cisco-duo-saml
Zimbra FOSS SAML