> two days ago i might have agreed with you. but putting resimprove-00 > into the blender and making me drink it has made me obstreperous as > follows: if an answer of <name,type=1,rrset> is in cache and you hear a > question for <name,type=2> and forward it and you then hear nxdomain, > then would you purge the <name,type=1,rrset> element when caching the > nxdomain for <name>, or would you retain the old type=1 element, such > that when the nxdomain expires, you could once again answer questions > for <name,type=1> using the <name,type=1,rrset> you started out with?
Sorry, I didn't mean to blow past this point. The correct answer depends on whether the two answers arrived in the correct order. If they did, purging the cached answer is a no-brainer. If they did not, caching the NXDOMAIN and purging the cached answer is wrong. But this has nothing to do with nxdomain-cut. RFC 2308 doesn't give any guidance on this; it seems obvious though that the spirit of the current state of the art is that the cached RRset should be purged--an out of order answer is quite a bit less likely than an in-order answer, and consistency is not paramount. _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
