On Feb 6, 2008 12:11 AM, Mark Andrews <Mark_Andrews@isc.org> wrote:
(from me) How does a cache-resolver know that it's time to issue a query with edns0?
cache-resolver that support EDNS0 will make EDNS0 queries by default. They will fallback to plain DNS if the query fails or they get a response that indicated the authoritative server doesn't support EDNS.
BIND's been making EDNS0 queries for ~8 years now. If your cache-resolver doesn't support EDNS it is long past time to upgrade.
excellent, thanks! (as always). Any thoughts on the possible lack of resilence from losing 9 server names/ips in the v4 to v6 move? (and I realize that later most/all root boxes will have both addresses)
It won't be a issue. IPv6 capable nameservers are supposed to use EDNS (see IPv6 node requirements). The roots can be tuned to preference A vs AAAA records. Most/all currently maintained caching servers support EDNS now or the next release will support EDNS. Mark -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: Mark_Andrews@isc.org