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NTP problem with system clock

Good day friends!

I have some problems with NTP and I don't understand how to solve this problem.

Network topology:

2 NTP servers in LAN ( and based on CentOS (Linux) - this ntp servers works properly.

I have got CISCO 2811 ( as call manager express.

this is part of my configuration CCME (works as tested router):


clock timezone UA 2 0                                                                                                                                                                                       
clock summer-time UA recurring                                                                                                                                                                                                              
clock calendar-valid                                                                                                                                                                                                                        
no network-clock-participate wic 0



  time-zone 28
  time-format 24
  date-format dd-mm-yy


ntp update-calendar
ntp server prefer
ntp server
time-range UA
absolute start 16:58 16 September 2010

[=== cut ===]

CCME#sh ntp status
Clock is synchronized, stratum 4, reference is
nominal freq is 250.0000 Hz, actual freq is 250.0000 Hz, precision is 2**24
reference time is D0418BE7.238D699D (10:29:43.138 UA Mon Sep 20 2010)
clock offset is 9.3351 msec, root delay is 57.77 msec
root dispersion is 87.24 msec, peer dispersion is 7.68 msec
loopfilter state is 'CTRL' (Normal Controlled Loop), drift is 0.000000007 s/s
system poll interval is 128, last update was 745 sec ago.

CCME#sh ntp associations

  address         ref clock       st   when   poll reach  delay  offset   disp
*~      3    123    128   377  1.228   9.335  7.680
+~      2     27    128   377  1.206  20.306  7.454
* sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured

CCME#sh ver
Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9-M), Version 15.1(2)T1, RELEASE SOFTWARE (fc1)
Technical Support:
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Wed 11-Aug-10 12:38 by prod_rel_team

CCME#sh inv
NAME: "2811 chassis", DESCR: "2811 chassis"
PID: CISCO2811         , VID: V05 , SN: FTX1236A25Z

NAME: "One port E1 voice interface daughtercard on Slot 0 SubSlot 0", DESCR: "One port E1 voice interface daughtercard"
PID: VWIC-1MFT-E1=     , VID: 1.0, SN: 35657653

NAME: "2nd generation two port FXS voice interface daughtercard on Slot 0 SubSlot 2", DESCR: "2nd generation two port FXS voice interface daughtercard"
PID: VIC2-2FXS         , VID: V01 , SN: FOC11300CPY

NAME: "PVDMII DSP SIMM with one DSP on Slot 0 SubSlot 4", DESCR: "PVDMII DSP SIMM with one DSP"
PID: PVDM2-16          , VID: V01 , SN: FOC12340CCY

NAME: "PVDMII DSP SIMM with Two DSPs on Slot 0 SubSlot 5", DESCR: "PVDMII DSP SIMM with Two DSPs"
PID: PVDM2-32          , VID: V01 , SN: FOC12373F1G

NAME: "16 Port 10BaseT/100BaseTX EtherSwitch on Slot 1", DESCR: "16 Port 10BaseT/100BaseTX EtherSwitch"
PID: NM-16ESW          , VID: V01 , SN: FOC12301RP2

NAME: "Power daughter card for 16 port EtherSwitch NM on Slot 1 SubSlot 0", DESCR: "Power daughter card for 16 port EtherSwitch NM"


So when I make "sh clock"

10:45:12.452 UA Mon Sep 20 2010
this is correct clock... but the system clock is:

Sep 20 07:45:26.960

(this is system clock that sends loginig and set up clock on the cisco phones) Difference of the real time and system clock time is 02:59:46

I don't understand where I make mistake or it is cisco bug?


Re: NTP problem with system clock

   Strange would think ntp update calendar would take care of that .  Try removing the clock calendar valid command don't think that needs to be there .

New Member

Re: NTP problem with system clock

Yes I try to do this, but the router don't change clock and calendar time....

The difference is 3 hours....

Clock time work properly, but the system messages and cisco phones work at the -3 hours from the true clock time... :(((((

I think that is cisco bug....

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