Re: [squid-users] No response from Squid when cannot resolve DNS for host

On 16/04/2012 8:52 p.m., Vincent Miszczak wrote:
> Hello,
>
> I have a strange issue with at least one URL :
> http://d.businessinsider.com/
>
> The host does not exist and cannot be resolved. But instead of telling me that Squid cannot resolve the host (as it does for example for the non existing http://zfsdfo.sdfdsfrgq.com/ ), Squid gives no response, and make the browser wait forever. This URL is included in the page : http://www.businessinsider.com/best-company-perks-2011-5 which never loads.
>
> While accessing the non existing URL, cache.log gives :
> 2012/04/16 10:48:06| ipcacheParse: No Address records in response to 'd.businessinsider.com'
>
> No message is logged when accessing another non existing host.
>
> Do I have a configuration issue or is this a Squid issue ?

This is a DNS configuration issue. Squid is a DNS client, not a
recursive resolver. It relies on your DNS server to perform all DNS
recursive lookups and identify the full response.

"No Address records in response" means that Squid received a possitive
response (domain *does* exist), but no IP addresses were supplied in
that response.

A quick dig shows:
"
; <<>> DiG 9.3.6-P1 <<>> d.businessinsider.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34561
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;d.businessinsider.com. IN A

;; ANSWER SECTION:
d.businessinsider.com. 86230 IN CNAME
businessinsider-d.openxenterprise.com.

;; AUTHORITY SECTION:
openxenterprise.com. 10630 IN SOA ns1-208.akam.net.
systems.openx.org. 2011062950 10800 3600 2678400 10800

;; Query time: 2 msec
;; SERVER: 209.169.0.1#53(209.169.0.1)
;; WHEN: Mon Apr 16 06:14:12 2012
;; MSG SIZE rcvd: 156
"

You will see this recorded as CNAME-only response count in your DNS stats.

Why its hanging I'm not sure. You should be getting that resolver error
page back from these as well.

Amos
Received on Mon Apr 16 2012 - 12:20:45 MDT