Configuring NTP on Cisco Device

Network Time Protocol (NTP) is a protocol for distributing the Coordinated Universal Time (UTC) by means of synchronizing the clocks of computer systems over packet-switched, variable-latency data networks.

I’ve tried to synchronizing on cisco router and workgroup-switch catalyst series. OK, let’s try!

1. Enter the privileged EXEC mode

   AND>enable

2. Enter the global configuration mode

   AND#configure terminal

3. Enter the command clock timezone zone hours-offsetin order to set the local time zone.

   AND(config)#clock timezone UTC 7 0

   Note: UTC for Jakarta – Indonesia

4. Enter the command clock summer-time zone recurringin order to specify daylight savings time. The default is that summer time is disabled.

   AND(config)#clock summer-time UTC recurring

5. Enter the ip address or hostname of peer in order to allow the clock on this router to be synchronized with the specified NTP Server.

   AND(config)#ntp server 0.id.pool.ntp.org

AND#show ntp associations
address         ref clock       st   when   poll reach  delay  offset   disp
~127.127.1.1     .LOCL.           7      5     16   377  0.000   0.000  0.236
*~119.252.169.31  203.89.24.34     3     45     64    37 17.190 -1423.1 439.32
* sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured

AND#show ntp status
Clock is synchronized, stratum 8, reference is 119.252.169.31
nominal freq is 250.0000 Hz, actual freq is 250.0025 Hz, precision is 2**24
reference time is D44515AC.DFAF0A26 (00:15:24.873 UTC Thu Nov 8 2012)
clock offset is -1423.1677 msec, root delay is 0.00 msec
root dispersion is 2.30 msec, peer dispersion is 190.11 msec
loopfilter state is 'CTRL' (Normal Controlled Loop), drift is -0.000010142 s/s
system poll interval is 64, last update was 140 sec ago.

Clock is synchronized!

AND#show clock detail
00:22:34.570 UTC Thu Nov 8 2012
Time source is NTP

AND#show calendar
00:23:33 UTC Thu Nov 8 2012