Authentication issues with server 2016

[Aaron]

Hi everyone

 

I just thought I would chance this and ask if anyone has had any issues with server 2016 and NTLM authentication at all?

 

I have setup a new server running 2016 and set this as a second domain controller (primary based at another site) both sites are connected via site-to-site and appear to be working fine. I have the users using the local dc as authentication but it appears that this isn't actually working. I tried to setup a radius server on my firewall again based at site B but authentication always fails. Also when the site to site failed (One morning) no one could authenticate with the local DC. I honestly cant seem to see any errors on the DC around authentication but this could be because its running auth through the site-to-site back to primary DC.

 

With the raidus once it was changed to for users to authenticate with the primary domain controller (Site A) the radius server worked perfect. As soon as I switch back to Site B domain controller it fails but again I cant see any errors to state that this has failed other than bring the site to site down and test again.

 

has anyone had any authentication issues at all running both a server 2012 and 2016 domain controllers?

 

Thank you.

[FN-GM]

Have you setup Active Directory Sites & Services properly? Are the domain controllers on separate AD sites? If so are you aware there is a replication delay, but this can be changed to a minimum of 15 minutes.

[Aaron]

Hi FN-GM thank you yes the servers are setup correctly within Active Directory Sites & Services, no the Domain controllers are on the same site Single domain different OU's. Replication was actually very quick during the initial DC replication and also time sync between both servers is grand.

 

It appears that the 2016 server doesn't seem to be accepting NTLM authentication for some reason