NIC Teaming MAC address use and management

Applies to: Windows Server 2016

When you configure a NIC Team with switch independent mode and either address hash or dynamic load distribution, the team uses the media access control (MAC) address of the primary NIC Team member on outbound traffic. The primary NIC Team member is a network adapter selected by the operating system from the initial set of team members. It is the first team member to bind to the team after you create it or after the host computer is restarted. Because the primary team member might change in a non-deterministic manner at each boot, NIC disable/enable action, or other reconfiguration activities, the primary team member might change, and the MAC address of the team might vary.

In most situations this doesn’t cause problems, but there are a few cases where issues might arise.

If the primary team member is removed from the team and then placed into operation there may be a MAC address conflict. To resolve this conflict, disable and then enable the team interface. The process of disabling and then enabling the team interface causes the interface to select a new MAC address from the remaining team members, thereby eliminating the MAC address conflict.

You can set the MAC address of the NIC team to a specific MAC address by setting it in the primary team interface, just as you can do when configuring the MAC address of any physical NIC.

MAC address use on transmitted packets

When you configure a NIC Team in switch independent mode and either address hash or dynamic load distribution, the packets from a single source (such as a single VM) is simultaneously distributed across multiple team members. To prevent the switches from getting confused and to prevent MAC flapping alarms, the source MAC address is replaced with a different MAC address on the frames transmitted on team members other than the primary team member. Because of this, each team member uses a different MAC address, and MAC address conflicts are prevented unless and until failure occurs.

When a failure is detected on the primary NIC, the NIC Teaming software starts using the primary team member’s MAC address on the team member that is chosen to serve as the temporary primary team member (i.e., the one that will now appear to the switch as the primary team member). This change only applies to traffic that was going to be sent on the primary team member with the primary team member’s MAC address as its source MAC address. Other traffic continues to be sent with whatever source MAC address it would have used prior to the failure.

Following are lists that describe NIC Teaming MAC address replacement behavior, based on how the team is configured:

In Switch Independent mode with Address Hash distribution

All ARP and NS packets are sent on the primary team member

All traffic sent on NICs other than the primary team member are sent with the source MAC address modified to match the NIC on which they are sent

All traffic sent on the primary team member is sent with the original source MAC address (which may be the team’s source MAC address)

In Switch Independent mode with Hyper-V Port distribution

Every vmSwitch port is affinitized to a team member

Every packet is sent on the team member to which the port is affinitized

No source MAC replacement is done

In Switch Independent mode with Dynamic distribution

Every vmSwitch port is affinitized to a team member

All ARP/NS packets are sent on the team member to which the port is affinitized

Packets sent on the team member that is the affinitized team member have no source MAC address replacement done

Packets sent on a team member other than the affinitized team member will have source MAC address replacement done

In Switch Dependent mode (all distributions)

• No source MAC address replacement is performed

Related topics

NIC Teaming: In this topic, we give you an overview of Network Interface Card (NIC) Teaming in Windows Server 2016. NIC Teaming allows you to group between one and 32 physical Ethernet network adapters into one or more software-based virtual network adapters. These virtual network adapters provide fast performance and fault tolerance in the event of a network adapter failure.

NIC Teaming settings: In this topic, we give you an overview of the NIC Team properties such as teaming and load balancing modes. We also give you details about the Standby adapter setting and the Primary team interface property. If you have at least two network adapters in a NIC Team, you do not need to designate a Standby adapter for fault tolerance.

Create a new NIC Team on a host computer or VM: In this topic, you create a new NIC Team on a host computer or in a Hyper-V virtual machine (VM) running Windows Server 2016.

Troubleshooting NIC Teaming: In this topic, we discuss ways to troubleshoot NIC Teaming, such as hardware, physical switch securities, and disabling or enabling network adapters using Windows PowerShell.

Get started with the macOS client

Applies To: Windows 10, Windows 8.1, Windows Server 2012 R2, Windows Server 2016

You can use the Remote Desktop client for Mac to work with Windows apps, resources, and desktops from your Mac computer. Use the following information to get started — and check out the FAQ if you have questions.

• Curious about the new releases for the macOS client? Check out What’s new for Remote Desktop on Mac?
• The Mac client runs on computers running macOS 10.10 and newer.
• The information in this article applies primarily to the full version of the Mac client — the version available in the Mac AppStore. Test-drive new features by downloading our preview app here: beta client release notes.

Get the Remote Desktop client

Follow these steps to get started with Remote Desktop on your Mac:

1. Download the Microsoft Remote Desktop client from the Mac App Store.
2. Set up your PC to accept remote connections. (If you skip this step, you can’t connect to your PC.)
3. Add a Remote Desktop connection or a remote resource. You use a connection to connect directly to a Windows PC and a remote resource to use a RemoteApp program, session-based desktop, or a virtual desktop published on-premises using RemoteApp and Desktop Connections. This feature is typically available in corporate environments.

What about the Mac beta client?

We’re testing new features on our preview channel on AppCenter. Want to check it out? Go to Microsoft Remote Desktop for Mac and select Download. You don’t need to create an account or sign into AppCenter to download the beta client.

If you already have the client, you can check for updates to ensure you have the latest version. In the beta client, select Microsoft Remote Desktop Beta at the top, and then select Check for updates.

Add a workspace

Subscribe to the feed your admin gave you to get the list of managed resources available to you on your macOS device.

To subscribe to a feed:

1. Select Add feed on the main page to connect to the service and retrieve your resources.
2. Enter the feed URL. This can be a URL or email address:
   • This URL is usually a Windows Virtual Desktop URL. Which one you use depends on which version of Windows Virtual Desktop you’re using.
     • For Windows Virtual Desktop (classic), use https://rdweb.wvd.microsoft.com/api/feeddiscovery/webfeeddiscovery.aspx .
     • For Windows Virtual Desktop, use https://rdweb.wvd.microsoft.com/api/arm/feeddiscovery .
   • To use email, enter your email address. This tells the client to search for a URL associated with your email address if your admin configured the server that way.
3. Select Subscribe.
4. Sign in with your user account when prompted.

After you’ve signed in, you should see a list of available resources.

Once you’ve subscribed to a feed, the feed’s content will update automatically on a regular basis. Resources may be added, changed, or removed based on changes made by your administrator.

Export and import connections

You can export a remote desktop connection definition and use it on a different device. Remote desktops are saved in separate RDP files.

To export an RDP file:

1. In the Connection Center, right-click the remote desktop.
2. Select Export.
3. Browse to the location where you want to save the remote desktop RDP file.
4. Select OK.

To import an RDP file:

1. In the menu bar, select File >Import.
2. Browse to the RDP file.
3. Select Open.

Add a remote resource

Remote resources are RemoteApp programs, session-based desktops, and virtual desktops published using RemoteApp and Desktop Connections.

• The URL displays the link to the RD Web Access server that gives you access to RemoteApp and Desktop Connections.
• The configured RemoteApp and Desktop Connections are listed.

To add a remote resource:

1. In the Connection Center select +, and then select Add Remote Resources.
2. Enter information for the remote resource:
   • Feed URL — The URL of the RD Web Access server. You can also enter your corporate email account in this field – this tells the client to search for the RD Web Access Server associated with your email address.
   • User name — The user name to use for the RD Web Access server you are connecting to.
   • Password — The password to use for the RD Web Access server you are connecting to.
3. Select Save.

The remote resources will be displayed in the Connection Center.

Connect to an RD Gateway to access internal assets

A Remote Desktop Gateway (RD Gateway) lets you connect to a remote computer on a corporate network from anywhere on the Internet. You can create and manage your gateways in the preferences of the app or while setting up a new desktop connection.

To set up a new gateway in preferences:

1. In the Connection Center, select Preferences > Gateways.
2. Select the + button at the bottom of the table Enter the following information:
   • Server name – The name of the computer you want to use as a gateway. This can be a Windows computer name, an Internet domain name, or an IP address. You can also add port information to the server name (for example: RDGateway:443 or 10.0.0.1:443).
   • User name — The user name and password to be used for the Remote Desktop gateway you are connecting to. You can also select Use connection credentials to use the same user name and password as those used for the remote desktop connection.

Manage your user accounts

When you connect to a desktop or remote resources, you can save the user accounts to select from again. You can manage your user accounts by using the Remote Desktop client.

To create a new user account:

1. In the Connection Center, select Settings >Accounts.
2. Select Add User Account.
3. Enter the following information:
   • User Name — The name of the user to save for use with a remote connection. You can enter the user name in any of the following formats: user_name, domain\user_name, or user_name@domain.com.
   • Password — The password for the user you specified. Every user account that you want to save to use for remote connections needs to have a password associated with it.
   • Friendly Name — If you are using the same user account with different passwords, set a friendly name to distinguish those user accounts.
4. Select Save, then select Settings.

Customize your display resolution

You can specify the display resolution for the remote desktop session.

1. In the Connection Center, select Preferences.
2. Select Resolution.
3. Select +.
4. Enter a resolution height and width, and then select OK.

To delete the resolution, select it, and then select —.

Displays have separate spaces

If you’re running Mac OS X 10.9 and have disabled Displays have separate spaces in Mavericks (System Preferences > Mission Control), you need to configure this setting in the Remote Desktop client using the same option.

Drive redirection for remote resources

Drive redirection is supported for remote resources, so that you can save files created with a remote application locally to your Mac. The redirected folder is always your home directory displayed as a network drive in the remote session.

In order to use this feature, the administrator needs to set the appropriate settings on the server.

Use a keyboard in a remote session

Mac keyboard layouts differ from the Windows keyboard layouts.

• The Command key on the Mac keyboard equals the Windows key.
• To perform actions that use the Command button on the Mac, you will need to use the control button in Windows (for example Copy = Ctrl+C).
• The function keys can be activated in the session by pressing additionally the FN key (for example, FN+F1).
• The Alt key to the right of the space bar on the Mac keyboard equals the Alt Gr/right Alt key in Windows.

By default, the remote session will use the same keyboard locale as the OS you’re running the client on. (If your Mac is running an en-us OS, that will be used for the remote sessions as well.) If the OS keyboard locale is not used, check the keyboard setting on the remote PC and change it manually. See the Remote Desktop Client FAQ for more information about keyboards and locales.

Support for Remote Desktop gateway pluggable authentication and authorization

Windows Server 2012 R2 introduced support for a new authentication method, Remote Desktop Gateway pluggable authentication and authorization, which provides more flexibility for custom authentication routines. You can now try this authentication model with the Mac client.

Custom authentication and authorization models before Windows 8.1 aren’t supported, although the article above discusses them.

To learn more about this feature, check out https://aka.ms/paa-sample.

Questions and comments are always welcome. However, please do NOT post a request for troubleshooting help by using the comment feature at the end of this article. Instead, go to the Remote Desktop client forum and start a new thread. Have a feature suggestion? Tell us in the client user voice forum.