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NTP messages

Can anyone tell me what this message means?  I occasionally get a burst of about 8 of them, spaced at 15-second intervals, on the console (or the term mon):

Oct 10 15:03:47.773: NTP Core (NOTICE): ntp_receive: dropping message: AM_NEWPASS, passive association disabled..

This on a Cat 3750X running 12.2(58)SE2.  In principle this switch is synchronised upwards to six servers at stratum 2 or 3, (with one particular server "preferred"), and horizontally with three of its peers.  All nine associations seem to be OK.  I notice there is no dot in front of the timestamp on the message, so in this case I don't think the switch has lost sync.

Also, why do the NTP messages on this platform come out only on the console, and not on the syslog?  I have "ntp logging" enabled.

Any NTP experts out there?

Kevin Dorrell


Everyone's tags (2)

Accepted Solutions
Hall of Fame Super Gold

NTP messages

Hall of Fame Super Gold

NTP messages

NTP messages

Thanks Leo, that gives me something to work on.  It looks like my Windows Domain Controllers are trying to peer horizontally with the switch.  That does not really make sense because the Windows Domain Controllers do not have a reference clock other than my four mutually peered switches.  Each burst of 8 messages corresponds to 8 NTP packets received from one or other Domain Ccontroller.

Do you have any idea why the designers of IOS on the Cat 3750 might have chosen to send NTP messages to console but not to syslog?  I do have "ntp logging" enabled.


Hall of Fame Super Gold

Re: NTP messages

Do you have any idea why the designers of IOS on the Cat 3750 might have chosen to send NTP messages to console but not to syslog?

I've never seen your error message before.  I'd be stupid to say "it could be an IOS bug" because I'm not using this version.

Our MS DC are using our InfoBlox as NTP servers.  I think it is well known how MS implements NTP/SNTP with their product.

The error message sounds like the DC is trying to peer to your switch but your switch is almost saying, "what are you talking about?  Your NTP packets do not look like the NTP packets I understand".

PS:  Thanks for the ratings, Kevin.