(fedora) Re: NTP problem

[Matthew Saltzman]

On Wed, 14 Feb 2007, Phil Meyer wrote:

> Jacob (=Jouk) Jansen wrote:
>> Chris wrote on 18:12:06.46
>> 
>> 
>>> On 2/12/07, Jacob (=Jouk) Jansen <joukj at hrem.nano.tudelft.nl> wrote:
>>> 
>> [snip]
>> 
>>>> I have a problem with NTP on a FC6 machine connected to a adsl 
>>>> connection.
>>>> When starting up the machine it tells me it fails to synch with the 
>>>> server
>>>> (it started doing this one or two months ago) after that is sais that 
>>>> ntpd
>>>> is started succesfully. I doubt this because I start noticing slight (1/2
>>>> minute) time differences with other machines.
>>>> 
>> [snip]
>> 
>
> Are you running NetworkManager?
>
> This is a problem with NetworkManager.  It starts AFTER ntpd.  The fix is to 
> cause ntpd to start after NetworkManager but that is not a good solution in 
> my mind.
>
> You are also supposed to be able to declare a server as 'dynamic' in 
> /etc/ntp.conf.  This does not seem to correct the problem for me.
>
> So, two options remain:
>
> 1. modify /etc/init.d/ntpd to start later.
> 2. start ntpd from rc.local, which runs last.
>
> Personally I hate to modify system files that I then have to track over 
> releases.  In either case, here, this is necessary. :(
>
> It is my opinion that the ntpd maintainer needs to start ntpd AFTER 
> NetworkManager.
>
> ntpd is: 58
>
> NetworkManager is: 98
>
> 99 is sorta conventionally held for local customized startups scripts, so I 
> don't know what would be best.  Obviously the NetworkManager maintainers feel 
> the need to start as close to the end as reasonable.
>
> So, I guess its best to:
>
> # /sbin/chkconfig ntpd off
>
> and then edit /etc/rc.local and add:
>
> service ntpd start
>
> to then end of it.

This won't work either.  The NetworkManager daemon starts on bootup, but 
no connection is made until a user logs in.

The correct solution is to use NetworkManagerDispatcher(1) to start ntpd 
when the connection is made.

Don't modify any system files or rc.local.  Just turn ntp off at boot and 
add a script to /etc/NetworkManager/dispatcher.d/ that runs "service ntpd 
start" when an interface is brought up and "service ntpd stop" when it's 
brought down.  Instructions in the man page.

>
> Good Luck!
>
>
>

-- 
 		Matthew Saltzman

Clemson University Math Sciences
mjs AT clemson DOT edu
http://www.math.clemson.edu/~mjs