On 8/26/2013 11:25 AM, Lukas Tribus wrote: > Hi! > > >> If this were the root cause, wouldn't the cURL call fail in the way way, >> regardless of the CURLOPT_SSL_VERIFYPEER value? In other words, it >> doesn't seem like changing this cURL option would change the number of >> backend processes required to handle the request(s). But I could be wrong. > > Yes, it there is a difference. CURLOPT_SSL_VERIFYPEER = true probably masks > your real problem, because it fails at SSL level (due to certificate > validation failure; after all, thats why you disabled it, right?).
That's correct! > So the HTTP request passes only when you disable certificate validation, > which is way you see the 504 error only when its disabled. That doesn't > mean there is a problem with curl or SSL. It means there is a problem > with your backend. > Okay; that makes sense. > > >> Any further troubleshooting tips would be much appreciated. > > Triple check that your backend can handle multiple requests simultanously > and that your script doesn't somehow create a deadlook (requesting the > output of itself). > Is there a prescribed mechanism for the former (ensuring that the backend can handle multiple requests simultaneously)? Or should I simply write a script that, for example, uses a combination of "while" and "sleep()"to force a lengthy execution time while outputting some type of progress to indicate that each instance of the script is "alive"? > Check FCGI logs. If that doesn't help, increment the debug levels on nginx > and FCGI. > By FCGI logs, you mean the PHP logs, correct? Unfortunately, they reveal nothing, even at maximum verbosity. I'll try increasing nginx's logging verbosity, though. > > > > Regards, > > Lukas Thanks for your helpful insights here, Lukas! -Ben _______________________________________________ nginx mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx
