[ntp:questions] Re: server's address in ntp payload?
mayer at ntp.isc.org
Sun Nov 27 01:57:14 UTC 2005
David Schwartz wrote:
> "Danny Mayer" <mayer at ntp.isc.org> wrote in message
> news:43876FE3.1010309 at ntp.isc.org...
>>As long as you don't receive packets on the wildcard addresses your
>>response will go out using the same address as the packet was received
>>on. It's the wildcard addresses that cause the problem and you cannot
>>know which address the kernel may choose.
> Right. RFC1123 says:
> * "SHOULD"
> This word or the adjective "RECOMMENDED" means that there
> may exist valid reasons in particular circumstances to
> ignore this item, but the full implications should be
> understood and the case carefully weighed before choosing
> a different course.
> When the local host is multihomed, a UDP-based request/response
> application SHOULD send the response with an IP source address
> that is the same as the specific destination address of the UDP
> request datagram.
> What this means is that a UDP-based request/response application must
> send responses with the source address that was the destination in the reply
> unless the full implications of not doing so are understood and the case is
> carefully weighed. Failure to do this is failure to comply with RFC1123.
> RFC1123 states the host *requirements* for being part of the Intenet.
Then you don't understand the paragraph you just quoted. SHOULD is a
recommendation and not a requirement. You cannot violate a
recommendation. You used the word "must" which is not in the section you
In any case we do do this.
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