Time and Date Properties

As shown in Figure 23-1, the first tabbed window that appears is for configuring the system date and time and the NTP daemon (ntpd).

To change the date, use the arrows to the left and right of the month to change the month. Use the arrows to the left and right of the year to change the year, and click on the day of the week to change the day of the week. Changes will not take place until you click the Apply button.

To change the time, use the up and down arrow buttons beside the Hour, Minute, and Second in the Time section. Changes will not take place until you click the Apply button.

	Note
	Changing the date and time will change the system clock as well as the hardware clock. Clicking Apply or OK is equivalent to executing the date and hwclock commands with the selected date and time.

The Network Time Protocol (NTP) daemon synchronizes the system clock with a remote time server or time source (such as a satellite). The application allows you to configure a NTP daemon to synchronize your system clock with a remote server. To enable this feature, click the Enable Network Time Protocol button. This will enable the Server pulldown menu. You can choose one of the predefined servers or type a server name in the pulldown menu. Your system will not start synchronizing with the NTP server until you click Apply. After you click Apply, the configuration will be saved and the NTP daemon will be started (or restarted if it is already running). If you want this daemon to start automatically at boot time, you need to execute the command /sbin/chkconfig --level 345 ntpd on to enable ntpd for runlevels 3, 4, and 5.

For more information on NTP, read the NTP documentation available in the /usr/share/doc/ntp-<version> directory.

The NTP server is written to the /etc/ntp.conf and /etc/ntp/step-tickers files.

Clicking the Apply button will apply any changes that you have made to the date and time, the NTP daemon settings, and the time zone settings. Clicking the OK button will apply the changes and then exit the program.

	Warning
	If you configured a medium or high security level during installation or with Security Level Configuration Tool, the firewall rules will block the connection to the NTP port. To allow NTP to work, run the Security Level Configuration Tool, select Customize, and add udp:ntp to the other ports.