PowerShell - Add AD Site Subnet

Last month I posted a script that report the Missing Subnets from the Active Directory. The script goes on each Domain Controllers and get the last x entries from the NETLOGON.log file.
Once this report is generated, you might want to check with your Telecom guy/team to get the correct network mask, correct site of each entries and fix this situation.

Reminder: Subnet objects (class subnet) define network subnets in Active Directory. A network subnet is a segment of a TCP/IP network to which a set of logical IP addresses is assigned. Subnets group computers in a way that identifies their physical proximity on the network. Subnet objects in Active Directory are used to map computers to sites.

Today I will show how to add those missing subnets in your Active Directory using PowerShell on Windows Server 2012 and Previous versions via ADSI.

PowerShell - Report the AD Missing Subnets from the NETLOGON.log

Today I will share with you a script that report the Missing Subnets detected in the NetLogon file(s) of your Active Directory Domain Controller(s).

Update: See my Github repository for the most recent version

Missing Subnets

When a computer is joined to a domain It knows for sure of which AD domain it is a member. However once the computer is joined to the domain, It may or may not know which AD site it belongs to. Even if it thinks it knows the AD site, it may not even be in the correct AD site (e.g. because it was moved, AD site was renamed, Subnet not declared, Subnet was removed from a site and add to another...etc.).