[dns-operations] A record round-robin behavior
jim at rfc1035.com
Fri Apr 21 11:06:32 UTC 2006
On Apr 21, 2006, at 10:01, Mark K. Pettit wrote:
>> I am not saying that randomizing data is a bad thing I am saying that
>> client should not count on an RR set being randomly shuffled.
> Yeah, obviously. I"m just trying to attempt to predict the
> behavior of BIND.
What's the point? If you agree that a client shouldn't rely on a
randomly ordered RRset, you're really agreeing that clients should
not expect any style of RRset ordering in DNS responses. In other
words you're trying to predict something that's inherently
unpredictable. Even though BIND's behaviour wrt RRset ordering is, as
a general rule, deterministic.
> In investigating this whole thing, I came across the "rrset-order"
> option in BIND 8, which I hadn't heard of before.
> This makes things even more confusing. According to the man page, the
> default rrset-order is "cyclic". To quote from the BIND 8.4.6 man
> This implies to me that if I don't have an "rrset-order" statement
> in my
> named.conf file, A record round-robins should be returned in a
> fashion. That is not the behavior I see.
> Anyone have any idea why that might be?
Perhaps it's because the server you're querying (or the servers
they're querying) don't run BIND 8.4.6. Or something else is making
queries for the same name/class/type tuple in between the times you
make those queries. Or maybe there's some firewall/DNS proxy between
your client and the server that's interfering with the DNS traffic?
More information about the dns-operations