Hi Damien,
Thanks for reaching out and apologies for the delayed response.
I'm assuming you're referring to the Azure Active Directory single sign-on (SSO) connection with Salesforce, which allows your users to be automatically logged in to Salesforce with their Azure AD credentials and manage their accounts in one central location - the Azure portal.
Could you briefly explain that when you say I need this in the other direction as well, you mean AAD federation with Salesforce such that Azure AD users get access to Salesforce with their account but must manually maintain and retain Salesforce as the master accounting? If this is the case, you may set the Provisioning mode to Manual, as shown below, so that users' accounts are never auto-provisioned from Azure AD and must establish link and update it manually.
Or do you mean allowing Salesforce users to utilize their accounts to access Azure resources? If this is the case, you can configure federation using SAML/WS-Fed identity providers for guest users as described here In this example, Salesforce functions as the identity provider, but you must verify that Salesforce supports SAML identity federation.
Hope this helps
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