Skip to main content

How to find out which clients in your domain were added by an Authenticated User

In a Windows domain, all Authenticated Users have the ability to add up to 10 clients to the domain without contacting a Domain Admin. Here is how to find out which computers were added to your domain by your users.

On the Windows Server 2008 R2 Domain Controller, open PowerShell

Type Import-Module ActiveDirectory and press Enter

Type get-ADComputer –filter * –property ms-DS-CreatorSID where {‘$_.ms-DS-CreatorSID’ –like ‘*’} and press Enter.

Each computer that is listed has a value in the ms-DS-CreatorSID attribute. If the computer account was pre-created in Active Directory Users and Computers or manually joined by a Domain Administrator, a SID would not be present here. The SID is the SID of the user account that joined the computer to the domain.

OK, that was informative. You may be asking “How do I find out who added what?” The answer is in PowerShell. Sure, you could manually search each Computer account in Active Directory and record any ms-DS-CreatorSID attributes that you find. You could then manually look at the SID for each user and compare them. I would not waste my time that way. Here is a script that will do it for you. This is a PowerShell V2 script. Do not forget to run Import-Module ActiveDirectory into the PowerShell ISE before running this.


$CompList = Get-AdComputer –filter * –property ms-DS-CreatorSID | Select name, ms-DS-CreatorSID
$UserAccounts = Get-ADUser –Filter *
ForEach ($Comp in $CompList) {
ForEach ($User in $UserAccounts) {
$Test = $User.SID.Value
If ($Comp –like ‘*’ + $Test + ‘*’) {
Write-Host $User.Name Created $Comp.Name
}
}
}

The first line enumerates all the computer accounts in Active Directory. It includes the property ms-DC-CreatorSID since this attribute is not normally returned in this query. The data is the piped to the Select cmdlet so only the name and the SID is left.

Line 2 Enumerates all the user accounts in Active Directory and stores all the objectys in the variable $UserAccounts.

Line 3 cycles through each record from line 1 and examines them one at a time.

Line 4 cycles through each record of user accounts one at a time.

Line 5 creates a variable called $Test. This variable holds the value of the SID for the User account that is currently being examined.

Line 6 Compares the SID recovered from the creator of the computer account, and the users SID. The data from the computer account has some extra data in it. for that reason, we used wild card characters around the $Test variable so this extra data will not be of concern.

Line 7 writes who installed what to the display.
The remaining lines are syntax for closing the ForEach loops.

Comments

Popular posts from this blog

Adding a Comment to a GPO with PowerShell

As I'm writing this article, I'm also writing a customization for a PowerShell course I'm teaching next week in Phoenix.  This customization deals with Group Policy and PowerShell.  For those of you who attend my classes may already know this, but I sit their and try to ask the questions to myself that others may ask as I present the material.  I finished up my customization a few hours ago and then I realized that I did not add in how to put a comment on a GPO.  This is a feature that many Group Policy Administrators may not be aware of. This past summer I attended a presentation at TechEd on Group Policy.  One organization in the crowd had over 5,000 Group Policies.  In an environment like that, the comment section can be priceless.  I always like to write in the comment section why I created the policy so I know its purpose next week after I've completed 50 other tasks and can't remember what I did 5 minutes ago. In the Group Policy module for PowerShell V3, th

Return duplicate values from a collection with PowerShell

If you have a collection of objects and you want to remove any duplicate items, it is fairly simple. # Create a collection with duplicate values $Set1 = 1 , 1 , 2 , 2 , 3 , 4 , 5 , 6 , 7 , 1 , 2   # Remove the duplicate values. $Set1 | Select-Object -Unique 1 2 3 4 5 6 7 What if you want only the duplicate values and nothing else? # Create a collection with duplicate values $Set1 = 1 , 1 , 2 , 2 , 3 , 4 , 5 , 6 , 7 , 1 , 2   #Create a second collection with duplicate values removed. $Set2 = $Set1 | Select-Object -Unique   # Return only the duplicate values. ( Compare-Object -ReferenceObject $Set2 -DifferenceObject $Set1 ) . InputObject | Select-Object – Unique 1 2 This works with objects as well as numbers.  The first command creates a collection with 2 duplicates of both 1 and 2.   The second command creates another collection with the duplicates filtered out.  The Compare-Object cmdlet will first find items that are diffe

How to list all the AD LDS instances on a server

AD LDS allows you to provide directory services to applications that are free of the confines of Active Directory.  To list all the AD LDS instances on a server, follow this procedure: Log into the server in question Open a command prompt. Type dsdbutil and press Enter Type List Instances and press Enter . You will receive a list of the instance name, both the LDAP and SSL port numbers, the location of the database, and its status.