Re: (DNS) consensus wording
Koen Holtman (koen@win.tue.nl)
Mon, 1 Apr 1996 10:25:49 +0200 (MET DST)
David W. Morris:
>
>It is my understanding that MUST and SHOULD are defined terms and
>strongly encouraged is not as far as RFCs are concerned.
Yes. `strongly encouraged' seems to be a HTTP invention. I don't see
this as a real problem, but it you would rather see SHOULD, that is
fine with me.
> Thus, I
>offer the following editorial alternative to Koen's suggestion (which
>I endorse):
>
> If a client caches the result of a DNS lookups, it should observe the
> TTL (Time To Live) reported by the DNS server. If the TTL value is
> not available, the client must not cache the result of a DNS lookup
> for longer than XX minutes. In either case, the client must immediately
> discard a name lookup result if a network error occurs when using the
> result to initiate a connection.
Your version looks OK to me.
I have no real rationale for my XX=10 minutes, other than that it
seemed like a good enough XX to allow load balancing between mirrors
through dynamic DNS remapping. Too high a value for XX (like the DNS
worst case default, if such a thing exists) would not sufficiently
encourage client authors in making code to get the real TTL.
>Dave Morris
Koen.