Basic concepts and definition of Active Directory (AD) - Windows Server Tutorial

- [Instructor] Welcome, everyone. Let's have a brief overview of Active Directory. So Active Directory is the directory system of Windows. So what is this directory system? So this is a directory system that holds all the information, what are the usernames, what are any internal ID, any information that you add for the user. It also holds the logical structure of your entire infrastructure. We'll talk more about it. So, basically, it has all your domain and forest information. And the way Active Directory actually holds all this information is through the structure that it has built in within the AD DS service. So AD DS service provides a method for storing this directory data, And AD DS service also provides you with the mechanism to control your access and authorization, which is one of the main functions of Active Directory. So two key things to take away from here is that Active Directory basically provides you with the infrastructure and database to store all the information. And the way Windows Server actually does that is through the AD DS service. So in this basically course, our first step will be to have a Windows Server and install that AD DS service on the server. So we'll start by having a Windows Server that already has the Windows 2025 installed in it. And then we will install AD DS service, which will install not just the AD DS service, but all the components that comes with the service. So all of those will be installed as Step 1 to creating a new forest and new Active Directory. So Step 2 will be to promote that server to a domain controller. A domain controller is the key part of the Active Directory system. When we want to create a new forest, or we want to add a new domain to an existing forest, we need to have a domain controller. So that is what we are going to do next, and then we can actually expand our Active Directory. So you don't necessarily have to expand your Active Directory. Even for organizations, it is perfectly fine to have a what we call a flat Active Directory structure, where there is just one domain, one forest, and you have multiple domain controllers. But if needed, you can add additional domain, such as it can be a child domain, or it can be a domain at the same level. So let's look at the structure and storage system of Active Directory. So the logical structure of Active Directory, we already kind of touched base on that. When you are just beginning, and you have just one server, and you have promoted the server to a domain controller, it will ask you to create a new forest. That is your top level or your base level infrastructure or logical structure. Within the forest, you can have multiple domain. Within each domain, you can have multiple organizational units. Again, organizational units are basically kind of like when you go to Active Directory Users and Computers, you feel like you're creating folders, but it provides you with a logical structure. So what are the key components of Active Directory? So Active Directory has schema that has all the attributes and specification for all the objects that are stored in Active Directory. You have basically the global catalog server that has the copy of everything in Active Directory. So all the domains, all the forest-related information, all the schema is in global catalog server. So basically, it has the query and indexing system built into it. And finally, since we have multiple domain controllers and multiple domains and all these different logical grouping, we need a replication service to replicate all this information. So the details of the Active Directory components, I don't want to read out every component, but the key thing to remember is that when you basically introduce a server and you promote it to a domain controller, this is is the server itself, and the domain controller is the physical component. And you can have a database or data stores, application server. All of these are physical component. And when we talk about domains, forests, OU sites, containers, these are logical components of Active Directory. So in short, we just had a brief introduction of Active Directory. I think that this would give you brief overview as well as if you already know it. Hope it's a good refresher. Now we are going to dive into the demo of installing Active Directory for Windows Server 2025.