On Mon, 2 Aug 2004 [EMAIL PROTECTED] wrote: > >On Sun, 1 Aug 2004, Jun-ichiro itojun Hagino wrote: > >> getaddrinfo() is not a DNS-only function; it can lookup hostname-to > >> address using /etc/hosts, NIS, LDAP, whatever you have. what value > >> would you put in to ai_ttl when the lookup is done by non-DNS method? > > > >-1, unless something else is provided? > > then what do you expect application to do with the data? when does > it expire? any fabricated value (-1, 0, whatever) in ai_ttl is > problematical to TTL-aware application, IMHO. what i'm suggesting > is to use DNS-only API like getrrrsetbyname() if you want TTL.
Let's assume that currently apps keep records forever, i.e., "-1" (infinite). If apps would use TTL info to requery the addresses now and then, telling them that a particular record has infinite lifetime (because lifetime information wasn't provided) seems like pretty much equal to the situation now -- i.e., it doesn't make situations worse. (And infinite would actually probably be rather accurate esp. with /etc/hosts). getrrsetbyname has the generic problem that the applications don't want to care about the lookup mechanism used. /etc/hosts or whatever is just as fine as DNS. Thus I think only apps which specifically know that they definitely want their answers to come from DNS (and not from hosts file or whateveR) can use getrrsetname. But I don't think the majority cares, or should need to care. -- Pekka Savola "You each name yourselves king, yet the Netcore Oy kingdom bleeds." Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings . dnsop resources:_____________________________________________________ web user interface: http://darkwing.uoregon.edu/~llynch/dnsop.html mhonarc archive: http://darkwing.uoregon.edu/~llynch/dnsop/index.html
