HTTPS POSTS sometimes not getting to apache On OS X 10.8.5, I have apache fronting a web app that communicates with Authorize.net. After Authorize.net completes a transaction it posts back to my app with confirmation information.

97% of the time this works fine. The 3% that doesn't work is a problem because a customer has paid for a transaction that my app doesn't know has completed.

The failed posts don't show up in apache logs. I've checked access, error and ssl_request log.

They do show up in the appfirewall.log, without anything looking any different about the successful posts vs the unsuccessful:

In this sample, the post at May 23 08:40:26 failed, the rest worked fine.

May 23 02:36:27 my-host.local socketfilterfw[111] &lt;Info&gt;: Allow httpd connecting from 12.12.123.123:2381 to port 443 proto=6
May 23 08:40:26 my-host.local socketfilterfw[111] &lt;Info&gt;: Allow httpd connecting from 12.12.123.123:3706 to port 443 proto=6
May 23 10:51:13 my-host.local socketfilterfw[111] &lt;Info&gt;: Allow httpd connecting from 12.12.123.123:1254 to port 443 proto=6


I'm looking for some help on where else I can look to see why apache isn't seeing these requests.

Thanks
This article walks through a series of approaches for debugging Apache httpd, Debugging Apache Web Server Problems:


  Debugging requests and responses
  
  When supporting web applications, there are times when a problem can
  be caused by an application server, proxy server or the web server
  itself. To troubleshoot these types of issues, it is useful to dump
  the HTTP requests and responses to isolate the problem to the local
  system, or a remote system. The apache web server module mod_dumpio
  can be used for this purpose, since it allows HTTP requests and/or
  HTTP responses to be written to the error_log.


Alternatively, is your httpd instance occasionally saturated with requests and dropping new connections?

The techniques in the link above should help you isolate which part is encountering problems.

Failing that, try the Webmasters StackExchange; you may find more experienced people there.