Time Sync

[John Haxby]

Tom Needs a Hat Mitchell wrote:

>On Mon, Mar 01, 2004 at 02:15:33PM -0500, Christopher Ness wrote:
>  
>
>>On Mon, 2004-03-01 at 11:09, Phil Hannent wrote:
>>    
>>
>>>I also am not bothered about running a time server, just really want it
>>>to sync on boot or every hour would be good enough.
>>>      
>>>
>>You could create a cron job in root and have it run daily.  Here's my
>>cron entry.  This runs every day at noon, to do this hourly change the
>>12 to a *.
>>    
>>
>>00 12 * * *  /usr/sbin/ntpdate -u -s -t 20 ntp.cpsc.ucalgary.ca....
>>    
>>

It's not clear to me why you would want to do this when configuring ntpd 
is so easy -- just run redhat-config-date and check "enable network time 
protocol".

If you want time synchronization on a dial-up connection (where you 
aren't connected all the time), then there are ntp alternatives that do 
a good job for that: chrony (http://chrony.sunsite.dk/) for example.   
Just having npdate change the clock periodically isn't all that good -- 
note that ntp (and chrony, I expect) use adjtime(2) to speed up or slow 
down time to keep the clock adjusted.

jch