Create a subnet in Active Directory Server 2003, 2008 and 2012

1. Open Active Directory Sites and Services.
   
2. In the console tree, right-click Subnets, and then click New Subnet.
   
   Where?
   
   
   • Active Directory Sites and Services/Sites/Subnets
     
3. In Address, type the subnet address.
   
4. In Mask, type the subnet mask that describes the range of addresses included in this subnet.
   
5. Under Select a site object for this subnet, click the site to associate with this subnet, and then click OK.
   

Notes

• To perform this procedure, you must be a member of the Domain Admins group or the Enterprise Admins group in Active Directory, or you must have been delegated the appropriate authority. As a security best practice, consider using Run as to perform this procedure. For more information, see Default local groups, Default groups, andUsing Run as.
  
• To open Active Directory Sites and Services, click Start, click Control Panel, double-click Administrative Tools, and then double-click Active Directory Sites and Services.