Have BTDT

1. you need to allow traffic from ANYWHERE  port 123 back to your external
IF

2. on a redhat system, if the file /etc/ntp/step-tickers exists, then ntp
will set the clock as a once off when starting. Get my step-tickers from
http://www.cyberpro.com.au/downloads/step-tickers , I use CSIRO as my once
off sync on boot.

3. If your read around, they say you shouldn't really sync with stratum 1
servers such as CSIRO.  There are many public stratum 2 servers.  They say
you should be syncing with three or more to ensure one doesn't screw you
because of a sysadmin error on their part.  I would not use the broadcast
method (one version of the redhat rpm did)  Get my /etc/ntp.conf file at
http://www.cyberpro.com.au/downloads/ntp.conf , I have all the public
servers in it (mostly commented out)

4. It takes some time for your server to become synced.  Use "ntptrace" to
find out.  If you have just started ntpd you will be at stratum 16 (the
lowest) on localhost.  Once you are synced it will do the following:

[root@chevy /etc]# ntptrace
localhost: stratum 3, offset 0.000003, synch distance 0.20709
ns.saard.net: stratum 2, offset -0.010029, synch distance 0.02847
tictoc.tip.CSIRO.AU: stratum 1, offset -0.014075, synch distance 0.00142,
refid 'ATOM'
[root@chevy /etc]#

My server sits at stratum 3, workstations are therefore stratum 4.

5. Microsoft Winblows XP, if you enter an IPADDRESS, it doesn't @#$ work!
(in my experience)
The Microsoft help is totally clueless (as usuall) but it does use ntp port
123 (i watched it with iptraf)
If you put in the hostname of your firewall/server, and try and manually
update, it probably will not work.
If you just ignore this, windows will update itself with your server
eventually

Hope this helps.

----- Original Message -----
From: "Howard Lowndes" <[EMAIL PROTECTED]>
To: "Mail List - SLUG" <[EMAIL PROTECTED]>
Sent: Monday, May 27, 2002 10:36 AM
Subject: [SLUG] ntp problems


> I have an ntpd daemon running on my gateway which syncs to external clocks
> OK, but when I try to do an ntpdate from an intranet workstation to that
> daemon then it comes back with:
>
>  no server suitable for synchronization found
>
> tcpdump shows the traffic between the ntp client and the ntp server as
> being OK and there is no internal filtering going on.
>
> I would prefer not to have the intranet workstations syncing with external
> clocks, I would prefer that they use my internal clock and only have that
> syncing.
>
> One thing I have noticed is that the ntpd daemon running on the gateway
> never gets above the minpoll frequency (minpoll 6 = 64 seconds), whereas
> another, totally separate, daemon that I have running elsewhere is
> consistently running at maxpoll (maxpoll 16 = 65536 seconds)
>
> Any clues out there?
>
> --
> Howard.
> LANNet Computing Associates - Your Linux people
> Contact detail at http://www.lannetlinux.com
> "Life is like a hot bath - it's great when you're in it,
>  but the longer you stay the more wrinkled you become."
>   - Garfield
>
> --
> SLUG - Sydney Linux User's Group - http://slug.org.au/
> More Info: http://lists.slug.org.au/listinfo/slug
>

-- 
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