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I have a newly installed Centos 5.2 box, everything seems working except ntpdate sync, I have done enable port 123 UDP to pass through the firewall. I have tried to use -u for unprivileged ports but still keeps throwing this error "no server suitable for synchronization found". Can anyone there help?

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What is in your /etc/default/ntpdate and /etc/ntp.conf files? What happens if you do ntpdate -q What happens if you run ntpdate with sudo? – Dennis Williamson Sep 16 '09 at 15:20
Have you also allowed the response packet back in through the firewall? – Thorbjørn Ravn Andersen Sep 16 '09 at 17:47
Yes, its enabled out and in – Rungano Sep 18 '09 at 12:22

Do you have a NTP server configured? ntpdate will display that error message if you don't have one... try


for starters.

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Using the public NTP pool is the way to go. Even better if you isolate it to the continent you are on. – Avery Payne Sep 18 '09 at 5:02

You could try to sync with an internal NTP server to sort out firewall problems (every Windoze Domain Controller is also an NTP server, or install ntpd using yum).

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