You may come across the following alert in some of your Domain Controllers Event logs “Client IP Address does not map to an existing Site Boundary in Active Directory”
This event means that a machine has authenticated to a Domain controller which doesn’t have an IP range specified in AD Sites and Services subnets.
To find the IP of the offending machines you need to have a look at the domain controllers netlogon log (%systemroot%debugnetlogon.log) which will display a list of the IP addresses that do not have a subnet specified.
You then just need to open AD sites and Services and add the subnet.
- Open AD Sites and Services
- Expand Sites , Right click on subnets and choose new subnets
- Enter the Subnet and associate with the appropriate site and click ok
The error should now disappear