Can't get ntp to work

[Marcin Wisnicki]

My ntpd stopped synchronizing clock sometime ago (default ntp.conf).

To debug the problem I've tried running ntpdate and got strange results:

> # ntpdate 0.freebsd.pool.ntp.org
> 18 Oct 13:53:14 ntpdate[55102]: no server suitable for synchronization found
>	
> # ntpdate -u 0.freebsd.pool.ntp.org
> 18 Oct 13:53:19 ntpdate[55119]: adjust time server 193.25.222.240 offset 0.002672 sec


This would point to broken firewall BUT:

> # nmap -p123 -sU 0.freebsd.pool.ntp.org
> 
> Starting Nmap 6.49BETA5 ( https://nmap.org ) at 2015-10-18 13:52 CEST
> Nmap scan report for 0.freebsd.pool.ntp.org (193.25.222.240)
> Host is up (0.027s latency).
> Other addresses for 0.freebsd.pool.ntp.org (not scanned): 94.154.96.7 95.158.95.123 46.175.224.7
> rDNS record for 193.25.222.240: afrodyta.complex.net.pl
> PORT    STATE SERVICE
> 123/udp open  ntp
> 
> Nmap done: 1 IP address (1 host up) scanned in 0.64 seconds

So there is nothing blocking the traffic.

Any ideas ?