Recently I was doing so many tests on my ADFS lab and at one point, I basically got lost on my config and I did not remember what I had done. So, I got stucked in an ugly situation that my ADFS portal was not opening and it was giving an error in regards with TLS of my ADFS. Since I managed to fix that issue, I thought it is better to share this info with you in case you got yourself in same situation as me and you need a way out.
Before starting this topic, I need to tell you that I am planning to have a video in which I talk about the Password Through Authentication, so since that is the case, I am not going to talk on how PTA works. But instead, this post is going to be how PTA is related with Kerberos.
As you know, one of the things I enjoy doing in my lab, is to break things, and once they are broken enough, I start fixing them up. Sound quite masochist but that is one of the great ways to learn.
So, I was trying to break the relationship between an account in my on-premise environment and my Azure AD and try to re-establish it. However, it is not simple as I expected because you cannot do this in a proper way. Here is what I did to break everything and eventually fix them up.
Been away from writing articles, the reason behind this was because was my relocation to France and once you relocate to another country, all your plans are lost and it takes some times to get back on the track. So here I am now. :)
As you might already know, “Service Principal Names” plays an important role in authentication process of Active Directory. If you haven’t watched my video on Kerberos, I suggest you have a look at that video because I explain Kerberos and use of SPNs in Active Directory. However, I will produce a separate video dedicated to SPN later on, so make sure to follow my YouTube channel for more videos. Anyways, in this article, I am going to briefly talk about one of the common problems of authentication and consequently “Secure Channel” which falls to the category of “Duplicated SPN”.
https://jorgequestforknowledge.wordpress.com/2014/08/01/fixing-adsysvol-replication-and-reconnecting-a-disconnected-ad-domain-part-6/There are quite number of tasks in which an Active Directory administrator should always perform regularly during the day. These task can be varied from performing backups to troubleshooting serious problems of an Active Directory environment. Talking about tasks, some people tend to patrol through the different areas like ‘Event Viewer’ to find more information about the health of the infrastructure, some other people including me or maybe you, prefer to use other methods to do these same tasks with maximum efficiency. Some clear example of these methods are using SCOM or PowerShell scripting.
As everybody know, ‘Secure Channel’ in Active Directory is a key factor for initiating communication between domain controllers and clients. It’s crucial to understand what ‘Secure Channel’ is before jumping on troubleshooting the issues related to this concept. In this video firstly I explain briefly what secure channel is and how it is created. So if you always wanted to know how secure channel is created don’t miss the video.
Couple of days ago I noticed a strange behavior on network adapter of dozens of clients in my environment. The users were not able to authenticate to their workstations, throwing secure channel error. When one of the helpdesk administrators informed me about this issue, I thought it might be a typical problem of operating system including incorrect DNS configuration or duplicate names, but this was strange because basically everything related to secure channel were in place. Computer accounts were enabled in ADUC, DNS records existed, logintimestamps were updated and etc. So I tried digging in the problem to see what I can find.
Ever wondered why size of Active Directory database is different on domain controllers? You might ask yourself if Active Directory supports MultiMaster technology, then all objects reside in database on all domain controllers, so if that is true, why the size of database (NTDS.DIT) is completely different on one domain controller to another?
User authentication is one of the key principals of Active Directory as a directory system. It is safe to say that when user authentication does not exist in an Active Directory environment, then there is no need to have an Active Directory in our organization.