On Mon, Apr 13, 2015 at 11:17:41AM -0700, Frank Even wrote: > I have to apologize for that. I'd still definitely be curious to know > what info is stored in the ADB though since according to the docs ADB > was never intended to be flushed with a "flushtree" (although that has > now apparently been addressed in a new version as stated earlier in > the thread).
The ADB is the "address database"; it holds the addresses of previously encountered authoritative name servers and information about them such as whether they support EDNS and the largest packet size they're known to be able to accommodate. The "bad cache" is a separate collection of name server addresses that have been found to be irretrievably broken within the last several minutes. It prevents named from wasting too much of its time trying to get answers from broken servers. (The reason flushtree didn't originally clear those, if your curiousity extends this far, is that they're implemented as hash tables instead of trees like the DNS cache, so deleting all records below a given name is inefficient - it requires a linear search through the entire hash table. It turned out to be a useful thing to do, though, so we eventually decided to go ahead and put up with the inefficiency.) -- Evan Hunt -- e...@isc.org Internet Systems Consortium, Inc. _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users