On Sun, 23 Jan 2011, Shaojie Liu wrote:

> we setup our site with apache (2.2,mod_prefork only)+ PHP(5.2)+libcurl
> (version 7.16~7.21) and it used to work well under pretty high traffic for
> many months.

Let me mention that you send your question on the mailing list for the curl
command line tool while you seem to be having issues with the library (the
curl-library mailing list) or the PHP binding (the curl-and-PHP mailing list).

Using the correct mailing list will help you get a better and more accurate
answer and help.

> and then we've found recently that the curl_multi_* interface now throwing
> errno 6: name lookup timedout messages sometimes. service check performed to
> dns server shows little possibility to abnormal DNS service, and when we
> login to the server and manually made nslookup request, no problem found.
>
> the most weird thing is, the "name lookup timedout" could also be associated
> with not only remote servers but also "localhost" requests, like "
> http://localhost/http/service/param". and , all these issue gone after
> restarting apache. if not, the error message will keep printing.

When you post this question on a more suitable mailing list, it would be
really good if you would include information like what operating system you
use and what resolver backend in libcurl that is used.

Does this problem still occur if you use the latest version of libcurl?

-- 
  / daniel.haxx.se
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