[squid-users] Odd behavior on CNAME

[Alex Rousskov]

On 1/14/19 3:51 AM, Felix Falk wrote:

> I have a linkchecker running over Squid as forwardproxy. One Site is not
> longer existing but DNS still has a CNAME Record except the CNAME is
> pointing nowhere:
> 
>> $ host de.sitestat.com
>> de.sitestat.com is an alias for wildcard.sitestat.com.
>> $ host wildcard.sitestat.com.
>> $ 
> 
> If called via curl:
>> $ curl --proxy forwardproxy:3128 -v http://de.sitestat.com/
>> * About to connect() to proxy forwardproxy.rz.babiel.com port 3128 (#0)
>> *   Trying 192.168.110.215...
>> * Connected to forwardproxy.rz.babiel.com (192.168.110.215) port 3128 (#0)
>> > GET http://de.sitestat.com/ HTTP/1.1
>> > User-Agent: curl/7.29.0
>> > Host: de.sitestat.com
>> > Accept: */*
>> > Proxy-Connection: Keep-Alive
>> > 
> 
> The connection and this curl stays open for literally infinitely.
> (tested for 3 days).
> 
> In the Squid access.log nothing shows up. My cache.log has:
>> 2019/01/14 11:30:31 kid1| ipcacheParse: No Address records in response
> to 'de.sitestat.com'
> 
> Any ideas how to solve this or is this simply a bug?

I suggest reporting a bug if you can reproduce with the latest v4
release. Posting a (link to) compressed ALL,9 cache.log to bugzilla may
speed up triage.

FWIW, using v5-based code, your test worked for me with an immediate
ERR_CANNOT_FORWARD error and the following level-1 cache.log entry:

2019/01/14 09:04:58| DNS error while resolving de.sitestat.com: No valid
address records

Alex.