[ntp:questions] NTPD Sync. Problem

Steve Kostecke kostecke at ntp.isc.org
Tue Dec 19 14:35:03 UTC 2006

On 2006-12-19, Garrett <garrett.hennessey at gmail.com> wrote:

>     remote     refid   st t when poll reach  delay  offset jitter
>    .LOCL.  16 l    2   64  377   0.000   0.000  0.001

ntpd is not using the undisciplined local clock because it is operating
at Stratum 16. You need to modify your ntp.conf to fix this.

>  .LOCL.  1  u    5   64    0   0.000   0.000  0.000

ntpd has been able to establish an association with this server (because
the refid, stratum and type are set). But, as has been stated elsewhere,
ntpd has not received an NTP packet from during the last 8
poll intervals.

Have you checked the configuration of to ensure that you
are allowed access? is claiming to be a Stratum-1 server even though it is
"synced" to it's undisciplined local clock. This is generally frowned
upon since it can allow a low quality time source to masquerade as real
time source.

> I am running this on a linux system which I want to serve time to other
> computers on my local network when the primary time server is
> unavailable.

Just make sure that the strata of the undisciplined local clocks on both
time servers is _not_ the same.

> The linux system also should sync its time to  the primary
> time server when that computer is available (it won't be always), and
> when it's not available it should serve it's local time to the other
> clients on the network.

Please keep in mind that, in this configuration, the ntpd in the .150
server will be following that system's drifting mother board clock.
And the .161 server will either be following it's own drifting mother
board clock _or_ it will be attempting to converge on the .150 server's
drifting mother board clock. So the clients will be following a moving
target. Don't expect extremely tight coupling.

> Primary Time Server:
> The linux server IP:
> Here's my ntp.conf for the linux server:
> server
> fudge stratum 16

Change the 16 to 11 or 12.

> server

Append iburst to this line to speed up synchronization w/ this server.

> driftfile /var/lib/ntp/drift
> restrict mask nomodify notrap

This restrict statement is not breaking anything. But you've left the
default restriction, for everyone else other than,
_less_ restrictive. I'd change this to 'restrict default nomodify

> The other clients on the network are able to get time from the linux
> server,

The .161 server is unsynchronized. You clients should not be accepting
time from it.

> but it's serves the local time which is different from the time
> at

The .161 server can't serve time because it is not synchronized.

> It never updates it's local time to that of (primary
> time server).

Check the .150 server configuration.

If possible, post the .150 server ntp.conf file  and 'ntpq -p' billboard
so that we can see them.

> What am I missing here?

Some real sources of time.

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

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