Working with NIC Teaming in Windows Server 2012

Of the many networking features introduced in Hyper-V 3.0 on Windows Server 2012, several were added to enhance the overall capability for networking virtual machines (VMs). One of the features introduced in Hyper-V 3.0 is a collection of components for configuring NIC teaming on virtual machines and the Windows operating system.

Originally designed for Windows Server 2012, NIC Teaming can also be used to configure teamed adapters for Hyper-V virtual machines. Since our primary focus in this article is to provide an overview of NIC Teaming in Windows Server 2012 and later versions, we will not cover in detail the steps needed to configure NIC Teaming for operating systems and virtual machines.

In earlier versions of Hyper-V (version 1.0 and version 2.0), the Windows operating system did not provide any utility to configure NIC Teaming for physical network adapters, and it was not possible to configure NIC teaming for virtual machines. A Windows administrator could configure NIC teaming on Windows by using third-party utilities but with the following disadvantages:

• Support was provided by the vendor and not by Microsoft.
• You could only configure NIC Teaming between physical network adapters of the same manufacturer.
• There are also separate management UIs for managing each third-party network teaming if you have configured more than one teaming.
• Most of the third-party teaming solutions do not have options for configuring teaming options remotely.
  

Starting with Hyper-V version 3.0 on Windows Server 2012, you can easily configure NIC Teaming for Virtual Machines.

Making a Windows Server 2012 Domain Controller a Global Catalog Server

A global catalog server (GC) contains information about objects from all domains in an Active Directory forest. When you promote Windows Server 2012 to be a domain controller (DC), the option to make the new DC a global catalog server is selected by default. If you choose not to do this at the time of promoting the server to a DC, you can make the DC a global catalog server at a later stage.

Single-Domain Forest

In an Active Directory forest where there is only one domain, every DC can be a global catalog server without affecting performance. GCs are used when a client requests information about AD objects in different domains to avoid directing the queries to DCs in different domains until the right domain is located.

While DCs in a single-domain forest contain information about all AD objects, GC searches occur on a different port to standard AD queries, so you should configure every DC to be a global catalog server for load-balancing. If you make use of Universal Groups in AD, a global catalog is required for domain logons.
Multiple-Domain Forests

In general, you should consider having at least one global catalog server per AD site; but this will depend on whether clients and applications in a site need to look up information from different domains. If no GC is available, AD operations could be significantly slower if search queries have to be directed over a wide area network. GC placement in a multi-domain forest should take into consideration the increased replication overhead.

Make an Existing Domain Controller a Global Catalog Server

Log in to Windows Server 2012 with an account that is a member of the Domain Administrators group and follow the instructions below.

    * Open Server Manager from the icon on the desktop Taskbar or from the Start screen.
    * Select Active Directory Sites and Services from the Tools menu in Server Manager.
    * In the Active Directory Sites and Services console, expand the Sites folder and the site where the domain controller you want to make a global catalog server is located.
    * In your chosen site, expand the Servers folder and your chosen domain controller.
    * Right-click NTDS Settings under your chosen server and select Properties from the menu.
    * On the General tab of the NTDS Settings Properties dialog, check Global Catalog and click OK.



A DC won’t be marked as a GC in Active Directory until replication has completed, so you may need to be patient, depending on the speed of your network connections and number of objects in AD.