[ntp:questions] NTP Sync Problem

Per Hedeland per at hedeland.org
Sat Mar 10 00:17:55 UTC 2007

In article <d3074$45f12f5d$42865632$27653 at msgid.meganewsservers.com>
"Ron C." <nospam at nospam.com> writes:
>"Per Hedeland" <per at hedeland.org> wrote in message
>news:esq7cq$1qtc$3 at hedeland.org...
>> But I believe you said that it worked fine to do NTP requests from
>> inside your network (and I would expect that, as long as the router
>> doesn't try to NAT them to Couldn't you just set up an NTP
>> server there, and point the router at *that*? This would also have the
>> advantage that if the router goes berserk and starts spewing requests
>> continously, only you will suffer.:-)

>The problem causing the "cannot SEND" error message seems to be the
>originating IP rather than the destination IP.

Yes, I understood that much:-) - but most devices use the address
configured on the interface where the packets go out as source address.
Thus there is a significant probability that it will be able to send
through the internal interface - I believe you said that the internal
interface had a real address.

>  The Netopia router uses
>the WAN IP as the originating source.

But you've only seen this on packets going out the WAN interface, right?
Or rather, seen that packets fail to go out there...

>  I
>think the NTP program in the router stops in its tracks when it sees the
>private IP and produces the "cannot SEND" error message instead of
>sending the NTP request.

Extremely unlikely that they would have put such functionality into
their NTP implementation I think, it's probably rather the TCP/IP stack,
or an internal firewall, that refuses to send the message with that
"bogus" source address (or

>  It's probably not going berserk

Not yet.:-)

--Per Hedeland
per at hedeland.org

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