Hi , We have query related to Apache(httpd)-Tomcat communication and following are the details.
*Our configuration:* We have a web based tool where request to Tomcat service is send through apache using proxy. i.e., when some one selects a service on web page, apache acts as an interface where it forwards the request to Tomcat and then send back response from tomcat to web interface. *Apache configuration:* ProxyPass /reqheader/* https://localhost:PORT_X/reqheader/* ProxyPassReverse /reqheader/* https://localhost:PORT_X/reqheader/* Here PORT_X port is used by tomcat service. *Query:* When apache is trying to connect to backend server Tomcat at port PORT_X, Sometimes that request fails and we get "Service temporarily unavailable" message. When "Service temporarily unavailable" issue is hit, we are seeing following below message in error_log [Mon Apr 20 14:45:06 2015] [error] (239)Connection refused: proxy: HTTPS: attempt to connect to 127.0.0.1:PORT_X (localhost) failed [Mon Apr 20 14:45:06 2015] [error] ap_proxy_connect_backend disabling worker for (localhost) By the error message it seems that whenever apache is trying to connect to tomcat at port PORT_X and if there is no service running at this port then this issue is hit. I have tried to use retry=0 for PassProxy and it did not resolve the issue. i.e, ProxyPass /reqheader https://localhost:PORT_X/reqheader retry=0 *Below are my questions, can you please clarify*. 1. what can cause this issue? 2. How to identify exact root cause? 3. If this is known issue, is there any fix(configuration parameter or patch ) available? Also, please provide any reference documents for the same Thanks, Sandeep
