We are running a high volume portal that uses Apache 2.2.11 mod_proxy to reverse proxy content from downstream apache-> application servers, we recently started observing 503 errors on the Apache which happen sporadically throughout the day during activity on random requests. The requests returned with 503 don't appear on the backend apache access logs at all, there are no 503 failures on backend apache.Network traces of connectivity between frontend apache & the backend don't reveal anything either. An interesting pattern is the failed requests always take ~3-4 seconds Frontend Apache: Error log: [Wed Jul 14 15:59:46 2010] [error] (110)Connection timed out: proxy: HTTP: attempt to connect to 1xx.7x.xxx.xxx:80 (web.mycompany.net) failed [Wed Jul 14 15:59:46 2010] [error] ap_proxy_connect_backend disabling worker for (web.mycompany.net) Access log: "USER13" xx.xx.xxx.xxx - [14/Jul/2010:15:59:43 -0400] "GET /myapp/web/css/ext-all.css HTTP/1.1" 503 1030 3041412 Backend: This request never reached the backend server & doesn't shows up in the access logs of backend server All the failing requests like the above take ~3 seconds so i guess its like a timeout but i can't find any such configuration. Is there some known Apache bug for this behavior? We have retry=0 & disablereuse on for all proxy pass directives What kind of starvation should i look for in Apache we have mod_status enabled, file descriptor limit set a 64K, CPU is almost always idle & 25 Gig memory free on the server. Thanks --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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