Failure of server APACHE bridge::No backend server available for connection

Question

All,
I have an env: Browser -> OHS -> WLS(Apex Listener) -> Oracle DB.
If any SQL run for more than 5 mins, i get the below error.
Failure of server APACHE bridge:
No backend server available for connection: timed out after 10 seconds or idempotent set to OFF or method not idempotent.The only error i get is from the OHS's log
[2013-04-03T06:45:57.2946-05:00] [OHS] [ERROR:32] [] [core.c] [host_id: aa050] [host_addr: 121.146.60.102] [tid: 1260554560] [user: oracle] [ecid: 004qNDJn1du7m3KaETn3ES0004Ll00001T] [rid: 0] [VirtualHost: my.team.com:443]  ap_proxy: trying POST /pls/apex/wwv_flow.show at backend host 127.0.0.1/7003; got exception 'Backend Server not responding'; state: reading status line or response headers from WLS (wrote? Y read? N); not failing over because method not idempotent, referer: https://my.team.com/pls/apex/f?p=4500:1003:16571271664493::NO:::Is there a timeout variable other than the below in WLS?
Session Timeout (in seconds): 3600 .
TIA,
JJ

Answer 1

Regardless of the version, this is not exactly a "Forms" failure. This is an issue between OHS and WLS. Basically it means that OHS (via mod_wl_ohs) was unable to communicate with WLS_FORMS (or whichever managed server you are trying to access). Most often this means the managed server is not running or not responding. If you believe it is running and is responsive (test by hitting it directly) then the problem is probably related to your installation. Generally, if you have not properly configured your networking before you installed WLS and FMw, then this can occur. For example, on Windows machine which do not have static IP addresses, the Installation Guide instructs you to install the Windows loopback adapter and configure it. If you did not do this, OHS likely will not be able to contact WLS_FORMS.
You can test what I have described above by attempting to access WLS_FORMS directly. For example:
http://yourHost:9001/forms/frmservlet
If that works, the issue is probably related to a net config issue.
If you have access to MyOracle Support, refer to these notes:
<blockquote><li>Failure Of Server APACHE Bridge After Running Report From Forms 11gR2 on Windows 64-bit platform (Doc ID 1457845.1)
<li>Oracle Fusion Middleware 11g - Troubleshooting the Error "Failure of server APACHE bridge" (Doc ID 1304095.1)</blockquote>
The product Documentation Library can be found here:
http://docs.oracle.com/cd/E24269_01/index.htm