How to configure popular host-sharing services on a Mac

Erik Eckel lists the steps to enable two of the most popular host-sharing services on the Mac -- DVD/CD Sharing and Screen Sharing.

Most Mac users know they can share files between Macs. Few, though, understand how to configure host-sharing services or even why they might necessarily wish to do so.

The increase in the MacBook Air's popularity is just one trend driving the importance of host-sharing services, which make resources on one Mac available to others. In the case of the MacBook Air, another Mac might need to be configured to share its optical drive to provide the MacBook Air with access to a DVD or CD drive. Another common host-sharing service business users frequently need to configure is Screen Sharing. Let's take a look at both now (other host-sharing services include Printer Sharing, Remote Management, Scanner Sharing, Remote Login, and Xgrid Sharing).

How to configure DVD or CD Sharing

Also known as Remote Disk, DVD or CD Sharing enables making a Mac's optical drive available to other Macs. The service leverages Bonjour connectivity and does not provide access to any other information on the host computer. Further, user-specific access is not provided; the service is either on or off.

When the feature is enabled, the ODSAgent background service is started. The ODSAgent service listens for Remote Disk requests on randomly selected TCP ports. The service can only be accessed from other Macs from within their Finder sidebar, the Migration Assistant application, or the Remote Install Mac OS X program.

To enable DVD or CD Sharing, users should:

  1. Open System Preferences on the system that hosts the DVD/CD drive to be shared.
  2. Select Sharing.
  3. Check the box for DVD or CD Sharing.
  4. Ensure the Ask me before allowing others to use my DVD drive box is selected, if you wish to manually approve other Macs' access to the DVD/CD drive being shared.

Note that the Sharing console must be unlocked to enable configuration changes. If the console is locked, click the lock icon present in the bottom left-corner and provide the system administrator password to enable changing the DVD/CD Sharing settings.

Other users on the same network should then be able to see the DVD/CD by opening Finder on their Mac and clicking the computer hosting the shared DVD/CD drive from within the Shared console.

How to configure Screen Sharing

The Screen sharing host service enables users at one Mac to share their screen with a user at a second Mac. The service also enables the remote user to remotely control the Mac that is sharing its screen.

To enable screen sharing on a Mac, follow these steps:

  1. Open System Preferences.
  2. Open Sharing.
  3. Check the Screen Sharing box (again, note that the console must be unlocked to enable changing settings).
  4. Click the Computer Settings button and specify who may connect (Anyone and/or VNC viewers). If selecting VNC viewers, supply a required password.
  5. Within the Allow access for section, specify those user accounts that should be permitted to remotely connect to the system.

To connect to another Mac that has enabled Screen Sharing, follow these steps:

  1. Open Finder.
  2. Expand the Shared list.
  3. Select the Mac to which you wish to connect and click the Share Screen button.

An alternative connection method is to:

  1. Open Finder.
  2. Click Go and select Connect To Server.
  3. Enter the remote Mac's address (as displayed within the Screen Sharing console on the remote Mac) within the Server Address field and click the Connect button.

Note, when connecting to the remote Mac, you'll need to enter the username and password for a user account possessing permission to log in to the remote Mac computer.