I'm using Apache 2.2.3 as a front end for my application. I use mod_rewrite to reverse-proxy a path to a backend server. That works wonderfully, most of the time. But sometimes the requests are not sent to the backend server. Instead the Apache is returning a 400 error code to the client. The rewrite logs clearly shows that the post is processed and redirected
xxxx (2) rewrite '/myapp/security/json/UserLoginInitiate' -> 'http://myserver:1080/myapp/security/json/UserLoginInitiate' xxxx (2) forcing proxy-throughput with http://myserver:1080/myapp/security/json/UserLoginInitiate xxxx (1) go-ahead with proxy request proxy:http://myserver:1080/myapp/security/json/UserLoginInitiate [OK]
But the access_log shows:
IP - - [05/Dec/2012:19:37:18 -0500] "POST /myapp/security/json/UserLoginInitiate HTTP/1.1" 400 226
So it is returning a 400 error code to the client, and actually the request does not reach the backend server. This is happening for a small number of requests (maybe 10 a day, for a total of tens of thousands). Any ideas were to look?