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Re: round robin DNS without Ares only takes first IP

From: A Nonymous <anon_at_ymous.none>
Date: Thu, 28 Apr 2005 11:08:19 +0200

Hi folks

Dan Fandrich said he would expect the DNS server to return the list of
addresses in random order. I have been told that caching DNS servers are
not obliged to reorder the a-records, or you can not rely on it..

Daniel Stenberg wrote:

> On Wed, 27 Apr 2005, A Nonymous wrote:
>>> Alternatively I could count the number of addresses, choose the
>>> starting address, jump to the head after reaching the tail and
>>> terminate the loop when reaching the starting address again.
> But this will only change which address it starts trying on, not the
> order of the individual entries, right?

Absolutely. To change the order of the chain in a multithreaded
application I would have to reorder a copy of the address chain. We
could easily do this in case you prefer it. Personally I think it is not

Philippe Hameau spoke from my heart. Additionally reordering the whole
chain gets subordinated by the fact that connect retries are only needed
in case the first server is down or refusing connection.

best regards
A Nonymous
Received on 2005-04-28