Remote Control a Mac with Screen Sharing in OS X

Mac OS X includes a great feature called Screen Sharing which allows for the remote control of a Macs display. This means you can easily access a home or work Mac while on the go, or even do something like remotely troubleshoot a parents computer. It’ll work across just about any supported OS X versions too, a Mac running OS X Mountain Lion, Mavericks, and newer, can connect to a work Mac running Snow Leopard, and so on. Screen Sharing is extremely easy to setup, follow along or watch the video below for a quick demonstration.

How to Set Up & Use Screen Sharing in Mac OS X

To make things easy, the Mac screen being shared will be called the “server” and the other Mac connecting to it will be called the “client”. We’ll break this walkthrough into two parts, one for setting up the “server” and one for connecting to those servers with a “client”.

Enable Screen Sharing on the Mac whose Screen will be shared (as server)

• Open System Preferences from the  Apple menu and click on “Sharing”
• Check the box next to “Screen Sharing” to enable the feature on the Mac you want to share
• Set access as necessary by choosing “Administrators” or specifying a specific user that can remotely control the Mac
• Make a note of the Macs IP address, that is what you will be connecting to

With sharing enabled on the server Mac, now a connection can be made from the client Mac (or PC).

Connect to the Remote Mac Screen (as client)

From the Finder, hit Command+K or pull down the “Go” menu and bring up Connect To Server

• Prefixed with vnc:// enter the IP address of the Mac you want to connect to and control the screen of, for example:

vnc://192.168.1.50

• Authenticate according to the allowed users, and connect to the other Mac to control the screen

The client Mac will now connect to the server and you’ll quickly find the servers screen sitting in a window. Anything left open from the user you logged in as will be visible, and you have full access to everything on the Mac. With fast enough internet connections, there isn’t much lag in using the remote Mac at all, though it’ll likely be smoothest if connected over a LAN.

The video below demonstrates the connecting side of things:

With Mountain Lion, multiple people can connect to and observe the same Macs screen too, though if you’re trying to do a live screen cast you’d be better off using Google Hangouts. Also exclusive to OS X 10.8 and later is the ability to share files between Screen Shared Macs just by dragging and dropping, though if you don’t have that option there are other easy ways to share files too.

There are plenty of uses for remote controlling, it’s helpful when troubleshooting and diagnosing problematic Macs, remotely rebooting and sleeping Macs, and even provides a somewhat slow method to using a single keyboard and mouse to use different Macs, though sharing a keyboard is best done with an app like Teleport or Synergy.

Note that connecting to remote Macs may require additional steps if the machine is located behind a firewall or router. For example, if a Mac at home is connected to a wi-fi router with several other computers, the VNC port must be opened on the router so that the VNC connection can be made from a remote machine directly to the Mac. Because routers and firewall configurations are different from situation to manufacturer, it would be impossible to cover every example here, but users would typically would find such settings available under preferences named for ports, open ports, or port forwarding.

Finally, Screen Sharing is made even better because it uses VNC, a protocol which has clients available on virtually every platform. Because of VNC, a Mac can be remotely accessed and controlled from other devices like an iPad, iPhone, Android, Linux machine, and even Windows, all you need is a VNC client, of which there are many free varieties available.