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Ueli Zimmermann's avatar
Ueli Zimmermann
Brass Contributor
Jan 04, 2019

Azure MFA and Azure MFA Server side by side

Hello All,

 

Is it possible to use Azure Cloud MFA but for certain on Premise Apps which I'm not allowed or able to Publish through Azure App Proxy, use the Azure MFA Server within the same Tenant and same User IDs ?  or do I have to choose one or the other ?

 

Best regards

U

12 Replies

  • ThinkSync's avatar
    ThinkSync
    Brass Contributor

    Eli Shlomo  – thanks for sharing the links.

     

    Ueli Zimmermann - the Azure MFA feature program manager has some insightful comments on Reddit:

     

    https://www.reddit.com/r/AZURE/comments/7r4324/azure_mfa_server_on_premise_lifecycle_roadmap/

     

     “There isn't any engineering effort going into MFA server, and eventually it will end of life. All of our work is going into Azure MFA and features like conditional access policy...”

     

    “Eventually, yes, Azure MFA Server will probably be deprecated in favour of the cloud-only Azure MFA service. However, we wouldn't do this until we have feature parity in cloud-only Azure MFA, and a reasonable migration path. We also wouldn't do this without advance notice: I'm not completely sure (I'll find out and report back), but I'm pretty sure this will be at least 1 year. There are still some features we haven't quite finished yet which are only available in Azure MFA Server but not in the cloud-only service (PIN mode, pre-registration, OATH token support, etc.), but we're working on it.”

     

    So I wouldn’t be overly concerned if you’ve already deployed MFA Server, however to avoid migrating in the future, I’d recommend opting for the NPS extension or appliances that support direct Azure MFA integration.

     

    Hope this help,

    Matt

    • Eli Shlomo's avatar
      Eli Shlomo
      MVP

      Correct information but Reddit is not yet dependable information and not official by Microsoft, so for the different products its recommended to work according to Microsoft lifecycle information.

      I recommended avoiding working with NPS because isn't secure enough and it's better to work on top of SAML with Azure AD. (from experience on the field, the integration with NPS will fail on a first pen test because of the NPS itself and not the Azure AD)

       

      • ThinkSync's avatar
        ThinkSync
        Brass Contributor

        Eli Shlomo Sorry, I'll have to politely disagree :-)

         

        Looking at authentication from an architectural perspective, now that basic authentication can be blocked using conditional access, customers can start to move away from ADFS and start using Password Hash Sync…. but that's a topic for another thread :-)

         

        Righty hoo, NPS - completely agree the documentation is a little cryptic and if implemented incorrectly, could lead to credentials being sent over the wire in clear text. 

         

        1. In most cases we don’t need to perform primary auth against AD a second time or even at all. So, we set the policy to “Accept users without validating credentials”. (remember the NPS extension doesn't authentication users, it passes the request to the MFA Endpoint which triggers a user proof up - text, phone or auth app)
        2. Next, the NPS policy needs something to check, so we use a simple NASID condition, “MFA” as seen in the example below.
        3. As the RADIUS Access-Requests messages are processed without credential validation, we can switch the RAIDUS auth protocol to MSCHAP v2

         

        There’s a few more things to tweak on Netscaler and Windows which I’ll post in a blog later this week.

         

  • ThinkSync's avatar
    ThinkSync
    Brass Contributor

    Hello!

     

    Please try to avoid deploying the MFA Server. This product will be deprecated in the not to distant future.

     

    Have you considered using the Azure MFA NPS extension? I've recently deployed the extension for Citrix 2FA via Netscaler and it works really well. What workloads are you wanting to use MFA for?

    • Ueli Zimmermann's avatar
      Ueli Zimmermann
      Brass Contributor
      Thank you, we are currently use none specific Rules on ADFS except forward for MFA everything to Azure Cloud MFA Service. I would like to keep this way if possible and only utilize MFA Server for the stuff which does not pass ADFS directly. Example: we have Citrix NetScaler in front of On Premise Exchange 2016 which are able to use MFA Server for 2nd Factor. Exchange 2016 is Hybrid Configured with Exchange Online and we have Users there too which currently use ADFS/ Azure MFA Cloud based 2nd Factor. So the Way how still On-premise Users access the Environment is completely separated from WAP / ADFS. Is this possible or do I still need to somehow modify ADFS Claims ?
      • Eli Shlomo's avatar
        Eli Shlomo
        MVP

        You need to create an ADFS rule that avoids the request for the traffic that not pass ADFS directly, but in this configuration, you may create a lot of maintenance and management issues around this approach.

         

        Try to work with one IDP and point all application and requests to this IDP including on-premises.

         

         

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