Articles

Relationship between ‘SPN Duplication’ and ‘Domain Join’ process

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”.

Monitor health of DFSR and SYSVOL in your Active Directory

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.

Why secure channel can break in Active Directory?

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.

Can 'Unauthenticated' tag on NIC result to a broken secure channel?

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.

Why NTDS size is different on different Domain Controllers?

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?

Limit Active Directory user login to 1 session

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.

The auditor of auditors: 'LepideAuditor Suite'

Today, in modern days of technology, the concept of auditing has become one of the interesting facts in Information Technology (IT). Back in days, when I was probably playing with my SNES, the concept of auditing was so hard to follow with built-in applications and consoles, but today, you can find many applications which either covers a specific part of auditing or support a huge number of services and applications. Among them, it is rare to find a solution which covers a whole range of services and audits, but ‘LepideAuditor Suite’ is one of those rare. In this article we will talk about this application.

Protect your domain against WannaCry malware

As you all know the #wannacry malware hit the whole world in the last few days. The vulnerability behind this malware was leaked out by ShadowBrokers. Since the spreading rate of this vulnerability is greatly increasing, it is considered an obligation to prevent from this.

‘List Object Mode’ in Active Directory, a myth or future settings?

After long delay of being absent, I managed to fetch some time in order to pen down an article and share my thoughts about on of the features of Active Directory which has been always in total darkness for me. ‘List Object Mode’.

Fix Group Policy error 1058