Domino with Exchange online

Question

We are using domino server in our hq. but our sub is using m365.

To support encryption email between domino & M365, we are thinking about email with S/MIME.

Can M365 sync those info to onPrem LDAP server? Then our Domino server connect that onPrem LDAP server for those S/MIME info. Then our end user send encrypted email to M365 users.

Many Thanks.

Answer 1

Hi, @Jacky Lai

Yes, using S/MIME to encrypt e-mail communication between the Domino server and M365 is a viable approach. This involves the following steps:

1. Make sure that both your Domino and M365 users have a valid S/MIME certificate from a trusted certificate authority.
2. In M365, you need to publish the S/MIME certificate to a user profile in Azure Active Directory. Configure M365 to send and receive encrypted and signed email using S/MIME.
3. Use Azure AD Connect or a similar tool to synchronize the appropriate user attributes, including S/MIME certificates, from Azure Active Directory to the local Active Directory (AD). Ensure that the attributes used to map the S/MIME certificates stored in Azure AD to the correct attributes in the local AD.
4. Configure your Domino server to query your local LDAP server for S/MIME certificates. Ensure that your Domino server can access and use the S/MIME certificate from the LDAP server to encrypt and decrypt e-mail.

More information can be found Configure S/MIME in Exchange Online | Microsoft Learn

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