Error in cURL request: name lookup timed out - php

Question

I wrote some code that fill a login form and submit it via post method. Like:
$config = array(
'adapter' => 'Zend_Http_Client_Adapter_Curl',
);
$this->siteObj = new Zend_Http_Client('http://example.com', $config);
$this->siteObj->setCookieJar();
$this->siteObj->setUri('http://example.com/login');
$this->siteObj->setParameterPost( 'data[User][name]', 'user' );
$this->siteObj->setParameterPost( 'data[User][password]', 'password' );
$response = $this->siteObj->request('POST');
its works fine, but some times this error occur:
Error in cURL request: name lookup timed out
Error: An Internal Error Has Occurred.
whats the problem? what can I do to solve it?

Answer 1

I encountered the same problem:
From the shell, curl worked.
From the shell, the PHP script worked.
PHP could not ping the website.
The DNS config was right.
After restarting Apache, it worked. So strange.

Answer 2

It can be a timeout problem.
Try adjusting the connection timeout:
$config = array(
'adapter' => 'Zend_Http_Client_Adapter_Curl',
'timeout' => 100
);
you can also set single curl options:
$config = array(
'adapter' => 'Zend_Http_Client_Adapter_Curl',
'curloptions' => array(
CURLOPT_USERAGENT => 'Zend_Curl_Adapter',
CURLOPT_HEADER => 0,
CURLOPT_VERBOSE => 0,
CURLOPT_RETURNTRANSFER => 1,
CURLOPT_TIMEOUT => 10,
CURLOPT_SSL_VERIFYPEER => false,
),
);
If you find out that it is a timeout issue, I would not suggest to increase too much the timeout parameter, but rather to make a for loop with a number of retries.

Answer 3

It means that your DNS server failed to return a response in time. Check your DNS configuration (e.g. /etc/resolv.conf on Linux), and make sure they are alive and functional. Also try to ping the host in the URL from the same sever to get an idea whether the problem only in PHP or the any application running on the server (more likely).