Time Syncronization

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The '''Vera '''units use '''rdate '''to synchronize the time. Rdate is a client program which uses the Time protocol. Rdate servers must be running the Time service on port 37. Clients can use either TCP or UDP. This program conforms to RFC 868. The Time Protocol is not related or compatible with Network Time Protocol (RFC 958). This service does one time query and synchronization. Rdate use Time Protocol (RFC858) <u>'''which is not compatibile with ntpclinet/openntp'''</u> Network Time Protocol (RFC958). Time Servers are listenin on port 37 and Network Time Servers on 123.<br>  
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[[Category:How_To]]
 +
The '''Vera '''units use by default '''rdate '''to synchronize the time.<br> Rdate is a client program which uses the Time protocol and does one time query and synchronization. Rdate servers are running the Time service protocol on '''port 37''' which conforms to RFC 868. Clients can use either TCP or UDP.<br> The '''Time Protocol''' (RFC 858) is not related or compatible with '''Network Time Protocol''' (RFC 958) used by ntpclient/ntpd/openntp.<br>  
  
<u>To check the servers used to synchronize time use</u>&nbsp;:<br>  
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<br>  
  
'''rdate -p server'''
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== <span id="Prerequisites" class="mw-headline">Prerequisites</span>  ==
  
''The -p switch prints the date and time''.<br>
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*Vera hardware
 +
*Root acces to your OpenWRT
  
<u>To set the time from that server use this command:</u>  
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<br>  
  
'''rdate -l -s server'''
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== <span id="Instructions" class="mw-headline">Instructions</span>  ==
  
''The -l switch allows for logging results to Syslog, -s sets the system time.''
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Gain ssh access to your Vera (root) and use the password that is provided on the bottom of your vera2. More info on how to can be found here:[http://wiki.micasaverde.com/index.php/Logon_Vera_SSH [1]]
  
<br> There is no worldwide list of Time servers available. Many, but not all, Network Time Protocol (NTP) servers also serve Time on port 37. There is a list of NTP servers here&nbsp;: http://support.ntp.org/bin/view/Servers/WebHome<br>  
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Time Servers are listening on port 37 and Network Time Servers on 123.<br> '''Note:''' In order for you Vera unit to successfully syncronize its time you have to allow connections from it to the time servers on '''port 37 for rdate''' and '''port 123 for ntpclient''' if you install it.<br>  
  
The National Institute of Standards and Technology (United States Gov't) offers about a dozen Time servers to the public. Their server list is available here: http://tf.nist.gov/tf-cgi/servers.cgi#<br>  
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<u>Check if Vera can sync with a Time Server</u>&nbsp;:<br>
 +
<pre>rdate -p server</pre>
 +
''The -p switch prints the date and time from the server''.<br>  
  
Here is a list of working servers (at this moment):  
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<u>Set the time from a Time Server:</u>
 +
<pre>rdate -l -s server</pre>
 +
''The -l switch allows for logging results to Syslog, -s sets the system time.''
  
<br>  
+
There is no worldwide list of Time servers available. Many, but not all, Network Time Protocol (NTP) servers also serve Time on port 37. There is a list of NTP servers here [http://support.ntp.org/bin/view/Servers/WebHome [2]]<br>  
  
nist1.aol-va.symmetricom.com<br>nist1.columbiacountyga.gov<br>nist1-atl.ustiming.org<br>nist1-chi.ustiming.org<br>nist.expertsmi.com<br>nisttime.carsoncity.k12.mi.us<br>nist1-lnk.binary.net<br>wwv.nist.gov<br>time.nist.gov<br>utcnist.colorado.edu<br>utcnist2.colorado.edu<br>ntp-nist.ldsbc.edu<br>nist1-lv.ustiming.org<br>nist-time-server.eoni.com<br>nist1.aol-ca.symmetricom.com<br>nist1.symmetricom.com<br>nist1-sj.ustiming.org<br>nist1-la.ustiming.org<br>
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The National Institute of Standards and Technology (United States Gov't) offers about a dozen Time servers to the public. Their server list is available here [http://tf.nist.gov/tf-cgi/servers.cgi# [3]]<br>  
 
+
<br>  
+
  
 +
Here is a list of working servers (at this moment):
 +
<pre>nist1.aol-va.symmetricom.com
 +
nist1.columbiacountyga.gov
 +
nist1-atl.ustiming.org
 +
nist1-chi.ustiming.org
 +
nist.expertsmi.com
 +
nisttime.carsoncity.k12.mi.us
 +
nist1-lnk.binary.net
 +
wwv.nist.gov
 +
time.nist.gov
 +
utcnist.colorado.edu
 +
utcnist2.colorado.edu
 +
ntp-nist.ldsbc.edu
 +
nist1-lv.ustiming.org
 +
nist-time-server.eoni.com
 +
nist1.aol-ca.symmetricom.com
 +
nist1.symmetricom.com
 +
nist1-sj.ustiming.org
 +
nist1-la.ustiming.org
 +
</pre>
 
To test on your '''Vera '''unit which servers are working, log in by ssh and then create a new file called timeservers.txt in /tmp with this command&nbsp;:<br>  
 
To test on your '''Vera '''unit which servers are working, log in by ssh and then create a new file called timeservers.txt in /tmp with this command&nbsp;:<br>  
 
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<pre>touch /tmp/timeservers.txt
'''touch /tmp/timeservers.txt'''<br>  
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</pre>  
 
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Then edit it and copy the servers from the list using vim, and then run this command at least 5 times&nbsp;:<br>  
 
Then edit it and copy the servers from the list using vim, and then run this command at least 5 times&nbsp;:<br>  
 
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<pre>while read server; do echo -n "Server $server&nbsp;:"; rdate -p $server &amp;&amp; echo "OK" || echo "FAILED"; done &lt; /tmp/timeservers.txt
'''while read server; do echo -n "Server $server&nbsp;:"; rdate -p $server &amp;&amp; echo "OK" || echo "FAILED"; done &lt; /tmp/timeservers.txt '''<br>  
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</pre>  
 
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After that compare the results and pick the servers that only display OK, these will be the most reliable, and then add them to the list here /etc/config/timeserver .<br> '''Note: Please remember to keep the same format of the file when you edit it.'''
After that compare the results and pick the servers that only display OK, these will be the most reliable, and then add them to the list here /etc/config/timeserver .<br>  
+
  
 
To sync the time use the following command&nbsp;:<br>  
 
To sync the time use the following command&nbsp;:<br>  
 
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<pre>ash -x /usr/bin/sync_time.sh
'''&nbsp;ash -x /usr/bin/sync_time.sh'''<br>  
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</pre>  
 
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<br>  
 
<br>  
  
'''Creating a local timeserver'''
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== Creating a local time server<br>  ==
  
<br> If you want to create a local time servers you can use '''xinetd '''and you can read more about it here http://ecloud.org/index.php?title=Rdate_server <br>  
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If you want to create a local time servers you can use '''xinetd '''and you can read more about it here [http://ecloud.org/index.php?title=Rdate_server [4]]<br>  
  
 
Once all the settings have been made you need to restart '''xinetd '''by using this command&nbsp;:  
 
Once all the settings have been made you need to restart '''xinetd '''by using this command&nbsp;:  
 +
<pre>/etc/init.d/xinetd reload
 +
</pre>
 +
== '''<br>''' Installing the NTP client  ==
  
'''/etc/init.d/xinetd reload '''<br>  
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Optionally you can install the ntpclient also. Run the following commands to install the NTP client by ssh:<br>  
 +
<pre>opkg update</pre> <pre>opkg install ntpclient</pre>
 +
The ntp servers are define in this file&nbsp;: /etc/config/ntpclient
  
<br>  
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To edit the file you can use '''vim '''editor:
 +
<pre>vim /etc/config/ntpclient</pre>
 +
To view the current entries in it type:<br>
 +
<pre>cat /etc/config/ntpclient</pre>
 +
'''''Note: Please remember to keep the same format of the file when you edit it.'''''<br>  
  
<br>
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Check if Vera can connect to the default ntp servers&nbsp;: <br>
 +
<pre>BASE_NTP_SRV="openwrt.pool.ntp.org"; for i in 0 1 2 3 5; do NTP_SRV="$i.$BASE_NTP_SRV"; echo -n "$NTP_SRV&nbsp;: "; ntpclient -c 1 -p 123 -h $NTP_SRV || echo "FAILED"; done</pre>
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Force ntpclient to re-read the ntp servers and to do a time sync&nbsp;:
 +
<pre>/etc/init.d/ntpclient restart</pre>
 +
To check if the ntp client is running use this command&nbsp;: <br>
 +
<pre>ps fax | grep ntp</pre>
 +
If you see this message then you've successfully installed the NTP client:<br>
 +
<pre>4188 root      1068 S    /usr/sbin/ntpclient -i 600 -s -l -D -p 123 -h 0.openwrt.pool.ntp.org
 +
14454 root      1672 S    grep ntp</pre>

Latest revision as of 02:58, 15 June 2013

The Vera units use by default rdate to synchronize the time.
Rdate is a client program which uses the Time protocol and does one time query and synchronization. Rdate servers are running the Time service protocol on port 37 which conforms to RFC 868. Clients can use either TCP or UDP.
The Time Protocol (RFC 858) is not related or compatible with Network Time Protocol (RFC 958) used by ntpclient/ntpd/openntp.


Contents

[edit] Prerequisites

  • Vera hardware
  • Root acces to your OpenWRT


[edit] Instructions

Gain ssh access to your Vera (root) and use the password that is provided on the bottom of your vera2. More info on how to can be found here:[1]

Time Servers are listening on port 37 and Network Time Servers on 123.
Note: In order for you Vera unit to successfully syncronize its time you have to allow connections from it to the time servers on port 37 for rdate and port 123 for ntpclient if you install it.

Check if Vera can sync with a Time Server :

rdate -p server

The -p switch prints the date and time from the server.

Set the time from a Time Server:

rdate -l -s server

The -l switch allows for logging results to Syslog, -s sets the system time.

There is no worldwide list of Time servers available. Many, but not all, Network Time Protocol (NTP) servers also serve Time on port 37. There is a list of NTP servers here [2]

The National Institute of Standards and Technology (United States Gov't) offers about a dozen Time servers to the public. Their server list is available here [3]

Here is a list of working servers (at this moment):

nist1.aol-va.symmetricom.com
nist1.columbiacountyga.gov
nist1-atl.ustiming.org
nist1-chi.ustiming.org
nist.expertsmi.com
nisttime.carsoncity.k12.mi.us
nist1-lnk.binary.net
wwv.nist.gov
time.nist.gov
utcnist.colorado.edu
utcnist2.colorado.edu
ntp-nist.ldsbc.edu
nist1-lv.ustiming.org
nist-time-server.eoni.com
nist1.aol-ca.symmetricom.com
nist1.symmetricom.com
nist1-sj.ustiming.org
nist1-la.ustiming.org

To test on your Vera unit which servers are working, log in by ssh and then create a new file called timeservers.txt in /tmp with this command :

touch /tmp/timeservers.txt

Then edit it and copy the servers from the list using vim, and then run this command at least 5 times :

while read server; do echo -n "Server $server :"; rdate -p $server && echo "OK" || echo "FAILED"; done < /tmp/timeservers.txt

After that compare the results and pick the servers that only display OK, these will be the most reliable, and then add them to the list here /etc/config/timeserver .
Note: Please remember to keep the same format of the file when you edit it.

To sync the time use the following command :

ash -x /usr/bin/sync_time.sh


[edit] Creating a local time server

If you want to create a local time servers you can use xinetd and you can read more about it here [4]

Once all the settings have been made you need to restart xinetd by using this command :

/etc/init.d/xinetd reload

[edit]
Installing the NTP client

Optionally you can install the ntpclient also. Run the following commands to install the NTP client by ssh:

opkg update
opkg install ntpclient

The ntp servers are define in this file : /etc/config/ntpclient

To edit the file you can use vim editor:

vim /etc/config/ntpclient

To view the current entries in it type:

cat /etc/config/ntpclient

Note: Please remember to keep the same format of the file when you edit it.

Check if Vera can connect to the default ntp servers :

BASE_NTP_SRV="openwrt.pool.ntp.org"; for i in 0 1 2 3 5; do NTP_SRV="$i.$BASE_NTP_SRV"; echo -n "$NTP_SRV : "; ntpclient -c 1 -p 123 -h $NTP_SRV || echo "FAILED"; done

Force ntpclient to re-read the ntp servers and to do a time sync :

/etc/init.d/ntpclient restart

To check if the ntp client is running use this command :

ps fax | grep ntp

If you see this message then you've successfully installed the NTP client:

4188 root      1068 S    /usr/sbin/ntpclient -i 600 -s -l -D -p 123 -h 0.openwrt.pool.ntp.org
14454 root      1672 S    grep ntp
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