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22.14. Configure the Firewall to Allow Incoming NTP Packets
The
NTP traffic consists of UDP packets on port 123 and needs to be permitted through network and host-based firewalls in order for NTP to function.
22.14.1. Configure the Firewall Using the Graphical Tool
To enable
NTP to pass through the firewall, using the graphical tool system-config-firewall, issue the following command as root:
~]# system-config-firewall
The Firewall Configuration window opens. Select Other Ports from the list on the left. Click . The Port and Protocol window opens. Click on one of the port numbers and start typing 123. Select the “port 123” entry with udp as the protocol. Click . The Port and Protocol window closes. Click in the Firewall Configuration window to apply the changes. A dialog box will pop up to ask you to confirm the action, click . Note that any existing sessions will be terminated when you click .

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