How come I get 'no server suitable for synchronization found' from my NTP client when the server is returning a valid NTP response to the client? · May 4, 05:44 PM
This is one I hadn’t seen before last week. On our Solaris 9 clients, running
ntpdate -d -u ip.of.server
Kept on returning
no server suitable for synchronization found
even though the debug mode showed UDP responses coming back from the server. The server in question runs using UDP / unicast mode.
We used snoop to look at the NTP response
snoop -v -v port 123
(use -v -v to get the protocol decode output), and saw these suspicious field/value pairs:
NTP: Leap: 0x03 - clock unsynchronized
NTP: Reference clock: INIT
NTP: Reference time: 0x00000000.00000000
There were other headers, but they did not indicate problems. 0×03 in the Leap field, the INIT state, and a reference time of 0×00 indicated that the NTP server was not properly initialized / configured properly. Further investigation revealed that indeed, this was the case, the Sidewinder / G2 NTP server was not properly configured.
— Max Schubert
