[squid-users] Bizarrely slow, timing out DNS only via Squid 😖

[Dan Charlesworth]

Like this:

# time nslookup httpbin.org
Server:		192.231.203.3
Address:	192.231.203.3#53

Non-authoritative answer:
Name:	httpbin.org
Address: 54.175.222.246

real	0m0.026s
user	0m0.001s
sys	0m0.004s


# time dig httpbin.org

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.37.rc1.el6_7.6 <<>> httpbin.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44477
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 4

;; QUESTION SECTION:
;httpbin.org.			IN	A

;; ANSWER SECTION:
httpbin.org.		577	IN	A	54.175.222.246

;; AUTHORITY SECTION:
httpbin.org.		6161	IN	NS	ns-769.awsdns-32.net.
httpbin.org.		6161	IN	NS	ns-1074.awsdns-06.org.
httpbin.org.		6161	IN	NS	ns-410.awsdns-51.com.
httpbin.org.		6161	IN	NS	ns-1756.awsdns-27.co.uk.

;; ADDITIONAL SECTION:
ns-410.awsdns-51.com.	9966	IN	A	205.251.193.154
ns-769.awsdns-32.net.	13639	IN	A	205.251.195.1
ns-1074.awsdns-06.org.	11459	IN	A	205.251.196.50
ns-1756.awsdns-27.co.uk. 11489	IN	A	205.251.198.220

;; Query time: 21 msec
;; SERVER: 192.231.203.3#53(192.231.203.3)
;; WHEN: Thu Mar  3 17:03:04 2016
;; MSG SIZE  rcvd: 246

real	0m0.026s
user	0m0.004s
sys	0m0.001s


> On 3 Mar 2016, at 4:55 PM, Eliezer Croitoru <eliezer at ngtech.co.il> wrote:
> 
> Hey Dan,
> 
> What dig+nslookup queries did you tested for?
> 
> Eliezer
> 
> On 03/03/2016 07:39, Dan Charlesworth wrote:
>> Right now we have 1 squid box (out of a lot), running 3.5.13, which does something like this for every request, taking about 10 seconds:
>> 
>> 2016/03/03 16:30:48.883 kid1| 78,3| dns_internal.cc(1794) idnsPTRLookup: idnsPTRLookup: buf is 43 bytes for 10.100.128.1, id = 0x733a
>> 2016/03/03 16:30:48.883 kid1| 78,3| dns_internal.cc(1745) idnsALookup: idnsALookup: buf is 29 bytes for httpbin.org, id = 0x8528
>> 2016/03/03 16:30:48.883 kid1| 78,3| dns_internal.cc(1683) idnsSendSlaveAAAAQuery: buf is 29 bytes for httpbin.org, id = 0x69c2
>> 2016/03/03 16:30:48.884 kid1| 78,3| dns_internal.cc(1277) idnsRead: idnsRead: starting with FD 7
>> 2016/03/03 16:30:48.884 kid1| 78,3| dns_internal.cc(1323) idnsRead: idnsRead: FD 7: received 93 bytes from 192.231.203.132:53
>> 2016/03/03 16:30:48.884 kid1| 78,3| dns_internal.cc(1130) idnsGrokReply: idnsGrokReply: QID 0x733a, -3 answers
>> 2016/03/03 16:30:48.884 kid1| 78,3| dns_internal.cc(1195) idnsGrokReply: idnsGrokReply: error Name Error: The domain name does not exist. (3)
>> 2016/03/03 16:30:53.884 kid1| 78,3| dns_internal.cc(1384) idnsCheckQueue: idnsCheckQueue: ID dns8 QID 0x8528: timeout
>> 2016/03/03 16:30:53.884 kid1| 78,3| dns_internal.cc(1384) idnsCheckQueue: idnsCheckQueue: ID dns0 QID 0x69c2: timeout
>> 2016/03/03 16:30:53.885 kid1| 78,3| dns_internal.cc(1277) idnsRead: idnsRead: starting with FD 7
>> 2016/03/03 16:30:53.885 kid1| 78,3| dns_internal.cc(1323) idnsRead: idnsRead: FD 7: received 110 bytes from 172.16.100.4:53
>> 2016/03/03 16:30:53.885 kid1| 78,3| dns_internal.cc(1130) idnsGrokReply: idnsGrokReply: QID 0x69c2, 0 answers
>> 2016/03/03 16:30:58.885 kid1| 78,3| dns_internal.cc(1384) idnsCheckQueue: idnsCheckQueue: ID dns8 QID 0x8528: timeout
>> 2016/03/03 16:30:58.886 kid1| 78,3| dns_internal.cc(1277) idnsRead: idnsRead: starting with FD 7
>> 2016/03/03 16:30:58.886 kid1| 78,3| dns_internal.cc(1323) idnsRead: idnsRead: FD 7: received 246 bytes from 172.16.100.5:53
>> 2016/03/03 16:30:58.886 kid1| 78,3| dns_internal.cc(1130) idnsGrokReply: idnsGrokReply: QID 0x8528, 1 answers
>> 
>> AND YET, every nslookup or dig done at the command line on the same server is lightning fast. I’ve tried local and ISP-level DNS servers and get the same result.
>> 
>> What could be going on here?
>> 
> 
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