AD Connect auto login on prem apps?

Elyod used Ask the Experts™
We currently use Office 365 with AD Sync to hashes to keep our users accounts in sync with our on prem active directory accounts. One annoyance we've always had is if a user changes their password, they have to wait 30 minutes (the lowest time AD Connect will go to sync) for it to replicate. On top of it they have to re-sign into all of their on prem apps (Skype, Outlook, etc). We don't really care about the web login, but more so the on prem apps. While our users are "ok" so far with it, we want to streamline the experience for them. I recently was talking to another IT Admin about how they implemented AD Connect Pass Through Authentication, and he believes this is the solution we're looking for. So I Googled it and came up with this article: 

I was just curious if anyone else has experience with this? Is this the magic bullet we are looking for? Was it hard to implement?
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
Distinguished Expert 2018
Pass-through auth won't fix your problem(s.)

First, password syncing is not handled by the normal AADConnect sync schedule.  Passwords are synced near immediately.

From Microsoft's documentation:

The actual data flow of the password hash synchronization process is similar to the synchronization of user data such as DisplayName or Email Addresses. However, passwords are synchronized more frequently than the standard directory synchronization window for other attributes. The password hash synchronization process runs every 2 minutes. You cannot modify the frequency of this process. When you synchronize a password, it overwrites the existing cloud password.


Second, a password change, whether synced or via passthrough, still expires the kerberos ticket, which is what on-premises apps generally use. And that requires re-authentication.  This is by design and predates AADConnect by quite a bit.  So passthrough auth won't solve that issue.  It is just the way kerberos and Active Directory works.

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial