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!
- Enter the privileged EXEC mode
- Enter the global configuration mode
- 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
- 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
- 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 *~188.8.131.52 184.108.40.206 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 220.127.116.11 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