[ntp:questions] server's address in ntp payload?

Ulisses ulisses.alonso at unavarra.es
Fri Nov 18 07:28:29 UTC 2005


Hello Danny

On Thu, Nov 17, 2005 at 09:29:17PM -0500, Danny Mayer wrote:
> Ulisses wrote:
> > Hello all
[...]
> No you are not wrong, but why would you want to? 

The usefulness I wanted with it is to try getting the
loopback address of ntp servers running on routers

(for good purposes)

Also It would be useful if I could extract from ntp, any 
Globally Unique Identifier I could get from NTP protocol that
could identify the same ntpd process in a multi-homed router.

The only reliable way to achieve it I have figured out is 
(more or less) to extract the ntp stats and compare them when 
possible

> Are you asking about the server sending the packet? 

 Host A                         Host B (Router)

                     query
ntpdc/ntpq/ntpd --------------> ntpd
                <-------------
                     reply

I want to know from Host A, the address of Host B looking an ntp header

> We already know the IP address of the
> sending server. The recvfrom() code returns that information so you need
> not explicitly look at the header, recvfrom does that implicitly.

As you can see, that is not my question

Thanks so much for your comments

	Ulisses

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