Differences between revisions 8 and 9
Revision 8 as of 2009-11-27 08:27:55
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Editor: JariAalto
Comment: Fix typos: "ntpq- p" => "ntpq -p" etc.
Revision 9 as of 2010-01-27 19:49:22
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Editor: PaulBrossier
Comment: protect cron command with brackets
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 * [Troubleshooting] If you run '''ntpq -p''' and you get   * [Troubleshooting] If you run '''ntpq -p''' and you get
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 *Run   *Run
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#m h dom mon dow user command 57 5 * * * root /usr/sbin/ntpdate ntp.blueyonder.co.uk {{{
#m h dom mon dow user command
57 5 * * * root /usr/sbin/ntpdate ntp.blueyonder.co.uk
}}}

Translation(s): none

(!) ?/Discussion


  • Network Time Protocol, This will keep you system date with exact match to actual date.

Install and Configure

  • Type date to see current date and time

date
  • Install NTP

aptitude install ntp-simple
aptitude install ntpdate
  • Done.
  • Type ntpq -p to see servers you are syncing with.

  • Type date again to see if the time changed. You time should be synced in a next minute.

  • Done.

Troubleshooting

  • [Troubleshooting] If you run ntpq -p and you get

No association ID's returned
  • Run

dpkg-reconfigure ntp
  • And then again:

ntpq -p

     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 ntp.pbx.org     xx.xxx.xxx.xxx   2 u    -   64    1   33.763  1799619   1.054
 xray.metadom.co xx.xxx.xxx.xxx   2 u    1   64    1   40.367  1799619   0.001
 hydrogen.cert.u xx.xxx.xxx.xxx   2 u    -   64    1   64.740  1799619   0.001
 mirror          .INIT.          16 u    -   64    0    0.000    0.000   0.001

Add your time server

  • [Optional] If you would like to add a server that is closer to you and you know its address. You could type:

/etc/init.d/ntp-server stop
ntpdate clock.fmt.he.net
ntpdate ntp1.tummy.com
/etc/init.d/ntp-server start

Using The Cron

To configure the system to synchronize the clock with an Internet Time Server every morning, add the following entry to the /etc/crontab configuration file:

#m h dom mon dow user  command
57 5 *   *   *  root   /usr/sbin/ntpdate ntp.blueyonder.co.uk

Public Internet Time Servers

uk.pool.ntp.org (This points to a random United Kingdom based time server)