With just a bit of work in Terminal, though, you can set up a pool of time servers, so that if any one goes offline, another will be available to provide time services for your Mac. The key to this trick is the NTP Pool Project, which is a big virtual cluster of timservers. To use the , you need to set up a configuration file that points to a few of the NTP Pool Project's machines.

Open Terminal, and type cd /etc, and press Return. In that directory, you need to edit the ntp.conf file, and you need to edit it with root privileges via the sudo command: sudo nano ntp.conf, and provide your admin password when prompted.

When the file opens, delete the one line you see there, and then paste in the following text, assuming you're in the United States:

server 0.us.pool.ntp.org

server 1.us.pool.ntp.org