[ntp:questions] Re: Simple ntp setup, but I must be doing something wrong

Steve Kostecke kostecke at ntp.isc.org
Mon Aug 28 17:45:27 UTC 2006


On 2006-08-25, Jeff Boyce <jboyce at meridianenv.com> wrote:

> [root at Bison root]# ntpq -p
> remote           refid     st t when poll reach   delay offset jitter
>==============================================================================
>  rainforest.neor 0.0.0.0   16 u    - 1024    0    0.000 0.000 4000.00
 
I see this when I add rainforest to a running ntpd:

rainforest.neor 204.34.198.40 2 u  336 1024   7  115.059   16.906   0.074

> Aug 24 08:26:56 bison ntpdate[27483]: no server suitable for synchronization 
> found

This suggests that port 123/UDP is not open somewhere between your ntpd
and you remote time server(s).

Try 'ntpdate -d 216.176.180.82' to see if you can reach that server via
an unprivileged port (and some debugging output).

> My linux box is a Dell PE 2600 with RHEL 3 fully up to date (U8).  Therefore 
> my current version of NTP is  4.1.2-4.EL3.1.

The current stable version is 4.2.2

> The secondary time server listed in my config is from the stratum two 
> time server list on ntp.org.                                          

If you're depending on time servers maintained by others you really
should be using at least 4. That way your ntpd won't be led astray by a
false-ticker. An you'll have some backup in the event that one of your
remote time servers becomes unreachable.

> It is interesting to note that in my ntpq query this time server
> provides a listing of stratum 16, which I assume is why ntp is falling
> back to the local time clock.

The reason why your ntpd is using the "LocalCLK" is because your ntpd
can't talk to rainforest. Rainforest's stratum is displayed as 16
because your ntpd has not been able to determine what it really is.

FWIW: the rainforest looks fine from here ...

steve at durabook:~$ ntpq -p 216.176.180.82
remote           refid   st t when poll reach  delay   offset jitter
====================================================================
LOCAL(0)        LOCAL(0) 10 l    2   64  377   0.000   0.000  0.008
+ntp1.usno.navy. .IRIG.   1 u 1014 1024  377 191.491  38.566  3.022
*tick.usnogps.na .USNO.   1 u  451 1024  377  97.925 -11.827  1.071

steve at durabook:~$ ntpq -c "rv 0 stratum,peer,refid,state" 216.176.180.82
assID=0 status=06d4 leap_none, sync_ntp, 13 events, event_peer/strat_chg,
stratum=2, refid=204.34.198.40, peer=21838, state=4

> When I have substituted the ntp pool servers into my config file, then
> my ntp query shows that nothing is connecting (i.e., no astrix listed
> before any of the server names).

Do you see any indication in the ntpq -p billboard that the pool servers
are reachable?

You will need to let ntpd run for ~ 8 minutes before you will see the
talley codes (e.g. '*', '+', and so on). If you wish to reduce this time
you must append 'iburst' to your server line(s).

> Have I made a simple mistake somewhere in my config file?  I 
> thought I had it stripped down to the minimum.

Almost.

> [root at Bison root]# grep --invert-match ^\# /etc/ntp.conf
> restrict 127.0.0.1
> server 216.176.180.82

Append 'iburst' to this line for faster initial sync.

> server  127.127.1.0     # local clock
> fudge   127.127.1.0 stratum 10
> driftfile /var/lib/ntp/drift
> broadcastdelay  0.008

You don't need the broadcastdelay line unless this ntpd is a
broadcastclient _AND_ is unable to calculate the broadcastdelay.

-- 
Steve Kostecke <kostecke at ntp.isc.org>
NTP Public Services Project - http://ntp.isc.org/




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