External Authentication issues with Active Directory

[Hunor Dori]

Hi, I have a question about External Authentication

We have a Filemaker Server (19.3.2) on Windows 2016 Server, with Active Directory. Recently our Filemaker Apps started behaving weirdly.

Randomly, during login, the correct password is rejected. After 1-3 tries the system accepts it. The same issue happens with the native apps on Mac and Windows. Also, it's really slow during login. I assume it tries to authenticate.

I looked up the Event Viewer, there are a lot of failed attempts. In FM Server Log the connections keep dropping. Even if it's set to no timeout.

I think it might be some Windows AD issue, or some network related because I experiencing the same logging into the Admin Console. I tried to use just the user name or username@domainname.com.

We recently moved the DHCP server from a VM to our Firewall and had a power outage, where we had to restore one of the domain controllers. But we initiated several reboots, other systems are working fine.

Does anybody have a recommendation, idea or can someone please point me in the right direction? Thank you!

[Josh Ormond]

This definitely sounds like a DHCP or DNS issue. Unfortunately, without seeing more it's a little hard to diagnose. The best thing to do is start on the AD machine to verify logging in there works. Then move one layer out until you find where the issue is.

It really sounds though like there is a disconnect in the DHCP setup where things are point to the wrong place. Check all subnet masks, DNS Servers, Router Gateways... make sure they are all pointing to the correct places. Try flushing the dhcp ( by releasing the IP address and let it acquire it fresh )...at every step of the path between the client machine and the AD server.