I have somewhat neglected the topic of Active Directory here recently, so here is an easy introduction to the topic.
Foreword
This article is about the installation of a new Active Directory on a greenfield site. In this test environment, there is currently only one server that is to be upgraded to a domain controller and thus provides a new overall structure. Windows Server 2016 is installed on the server and, of course, all updates available at the time.
Preparation
The preparations are quickly completed. The server must be configured with an appropriate host name and have a permanently assigned IP address. In my case, I choose the host name FWDC1
I assign the IP address 172.16.100.11
Gateway and at least one DNS server should also be specified. In principle, these were all the necessary preparations.
Install Active Directory role
In order to install a new Active Directory, the "Active Directory Domain Services" role must first be installed:
The required features for the role are also installed:
The remaining queries can all be confirmed with "Next"
Finally, a summary is displayed
Once the binary data has been installed, the server can be upgraded to a domain controller and the Active Directory can be installed:
Upgrade domain controller
If the previous wizard window has already been closed, the wizard for upgrading to Domain Controller is also available in the Server Manager:
If you are on a greenfield site, you can freely assign the name for the Active Directory. In the meantime, names such as company.local are no longer used in new environments. A name like ad.firma.de would be better here. Nevertheless, names such as firma.local or firma.intern can still be used. However, the root domain name must not be one part. "Company" or "Internal" is therefore not possible.
I choose ad.frankysweb.com as the name:
The following dialog takes some time if no DNS delegation can be created; this is completely normal for the first domain controller and public DNS servers. In this case, this server is now trying to create a DNS delegation for ad.frankysweb.com in the frankysweb.com zone. Since frankysweb.com is hosted by a name server on the Internet and cannot be updated by this server, the creation of the delegation runs into a timeout.
Normally, delegation from the public DNS to the internal DNS is not required and you would hardly want to make the future DC accessible via port 53 (DNS) on the Internet.
The overall structure and domain function level can be set to "Server 2016" for a new environment. In this case, all Active Directory features will be available, but no server can be upgraded to a DC that does not use at least Server 2016 as its operating system.
Keep the password for the recovery mode in a SAFE place.
The following dialog also displays a corresponding message that no delegation could be created:
The NetBIOS name "AD" is quite nice, short, crisp and memorable. The first part of the root domain name becomes the NetBIOS name of the domain by default. In my case, this is "AD". However, the NetBIOS name can also be customized here:
Well, AD may mean something to every admin, but not to the users, the company name as NetBIOS name would also be conceivable.
The NetBIOS name is later used for the user names, for example "AD\frank". "frankysweb" can also be entered here as the NetBIOS name. The user name would then be "frankysweb\frank" or "frank@ad.frankysweb.com".
The storage paths can normally be left as they are:
Finally, a summary before the upgrade
Nice addition: The wizard also directly displays the PowerShell command for upgrading. This is very practical for new domain controllers.
Due to the DNS delegation, the prerequisite check also takes some time, the two warnings are normal.
After clicking on "Install", the server is upgraded to a domain controller and restarts.
After the restart, a few small adjustments are still necessary.
Reworking
The new domain controller is already functional, but there are still a few small finishing touches that are often forgotten.
Here again the example for the user name (as described above):
After the domain controller has been installed, a reverse lookup zone must be created:
The options can be adopted as far as possible, it is a primary zone:
The zone should be replicated to all DCs in this domain:
As type IPv4:
Only the subnet must be specified here:
Only secure dynamic updates are permitted, i.e. only domain computers are allowed to update their own DNS records.
After the reverse lookup zone has been created, the "Update corresponding pointer entry" checkbox is activated on the Host-A entry of the domain controller:
Checking the box then creates a PTR for the DC in the reverse lookup zone:
After the reverse lookup zone has been created, the subnet for the Active Directory location must be created, which is often forgotten:
The corresponding subnet or subnets for which domain controllers are responsible at this location are also specified here. In my case, this is only 172.16.100.0/24
We therefore have an Active Directory site with a domain controller for the subnet 172.16.100.0/24
By the way, it is a good idea to protect all organizational units from accidental deletion, this is done with a small Powershell command and can do no harm:
Get-ADOrganizationalUnit -filter * -Properties ProtectedFromAccidentalDeletion | where {$_.ProtectedFromAccidentalDeletion -eq $false} | Set-ADOrganizationalUnit -ProtectedFromAccidentalDeletion $true
One important thing at the end: the time!
The time in the Active Directory is still extremely important. A domain controller should therefore be synchronized with a time server. In this environment, there is only one domain controller so far, so the question of which DC needs to be synchronized with an external time source does not arise here. If there is more than one DC in the domain: The DC with the FSMO role "PDC" is synchronized with a time source:
To set an NTP server on the PDC, the following two commands are sufficient:
w32tm /config /manualpeerlist:ptbtime1.ptb.de /syncfromflags:manual /reliable:yes /update net stop w32time && net start w32time
The rework has been completed so far and the Active Directory is basically usable. However, as the Active Directory is a, if not the, core component in most companies, it is advisable to install at least two domain controllers.
The installation of a second domain controller follows in the next article.