Subject: Re: rc.d: time synchronization issues at boot time
To: Alistair Crooks <>
From: David Brownlee <>
List: tech-userlevel
Date: 03/16/2005 10:57:40
On Wed, 16 Mar 2005, Alistair Crooks wrote:

> Luke and I went round this discussion a few times yesterday (it was
> my original gripe about ntpdate and named).
> It seems that there are a number of ways to fix the root of the problem:
> 1. write a minimal name resolution service which would just do
> lookups, no zone transfer or any of the other things that the
> full DNS does. Use this to resolve hostnames before the full
> name service is started.
> 2. bring up dns, resolve the names of the time server, stop dns,
> get a good time value from the ntp server, set time, and re-start
> dns. Repeat for kdc and whatever else needs good time.
 	Why would you need to restart anything else, assuming you do
 	named -> ntpdate -> named restart -> everything else

> 3. forget about problems with time in kdc or named. (I'm not really
> serious here)
> 4. use dotted quads to resolve a time server (I'm not really serious
> here either, due to the dynamic behaviour of the ntp pool)

 	Variation on this - cache the previous dotted quads values
 	from the ntp pool and use them in ntpdate, then start ntpd
 	after named. _slightly_ better...

> 5. some other means I haven't thought of

 		David/absolute       -- No hype required --