Re: HAProxy and DNS

From: Krzysztof Olędzki <ole#ans.pl>
Date: Tue, 28 Sep 2010 15:34:13 +0200

On 2010-09-28 14:47, Guillaume Bourque wrote: > Hi Krzysztof
Hi Guillaume,

> Can you tell us which product you are using to answer dns request to > achieve a 1000 req / sec.

1k rps is rather small load so I use isc-bind.

Like I said - I have 4 servers, so each needs to handle only ~250 or ~340 requests/sec max. ~340 in a situation when one server is down due to mainanatce or malfunction. Most of the queries are recursive.

This is not very much comparing to ISC benchmark (93k rps [1]) but my servers are noticeably slower (older) and also need to handle additional load (NTP, WINS, etc). Hopefully simple benchmarks (queryperf for example) show that with 1kqps I'm still far enough from the limit. ;)

[1] ftp://ftp.isc.org/isc/dns_perf/ISC-TN-2008-1.pdf

> Krzysztof Olędzki a écrit :

>> On 2010-09-28 10:51, Hamnedalen, Mikael wrote:
>>> Hi.
>>>
>>> Anyone used HAProxy to load balance DNS requests ?
>>
>> It can't work. HAProxy is a http load balancer with tcp support, DNS
>> is mainly UDP based with TCP fallback.
>>
>>> I tried
>>>
>>> # DNS
>>>
>>> frontend dns_front
>>>
>>> bind 10.216.208.20:53
>>>
>>> default_backend dns_serv
>>>
>>> backend dns_serv
>>>
>>> server dns1 192.176.113.155:53 check
>>>
>>> server dns2 192.176.113.156:53 check
>>>
>>> # DNS END
>>>
>>> But it didn’t work. Any ideas, or any hints for any other product ?
>>
>> LVS + Keepalived. Works like a charm. I have two 2 (active/backup) and
>> 4 realservers handling up to 1000 DNS req/sec.

Best regards,

                        Krzysztof Olędzki Received on 2010/09/28 15:34