Resolving timed out after 5000 milliseconds

Hi, any server guys out here?

I have a PHP cURL question: what could it be, if I’m getting “Resolving timed out after 5000 milliseconds” error, but only for part of my requests?

I.e., it is the same domain every time, but only in small fraction of requests curl cannot resolve it…

Is it definitely resolving problem or could it be something related to PHP code?

How can I even approach to troubleshooting it? (wherever I’ve googled — there seem to only be answers for when the site is steadily unaccessible…)

Another question: Can PHP cURL use kind of caching for the resolving (besides CURLOPT_RESOLVE, as I don’t want my application to be responsible for the “serverly” stuff of this level…)?

getting many problems with this lately… :/