NO_RESOURCES Errors in APACHE when WLS at Backend

At times you will see, apache throws no resources error when you have weblogic in backend.

    

a snippet of error as below:   

weblogic: *******Exception type [NO_RESOURCES] (apr_socket_connect call failed with error=70007, host=xx.xx.xx.xx, port=xxxx) raised at line xxxx of URL.cpp

ex:
[DATE TIME] [error] [client X.X.X.X] ap_proxy: trying POST /xxx/xxxx/xx at backend host 'X.X.X.X/xxxx; got exception 'NO_RESOURCES: [os error=115, line 1602 of URL.cpp]: apr_socket_connect call failed with error=70007, host=X.X.X.X, port=xxxx ', referer: http://xxxx.x.xxx/xx.html#

This usually occurs when WLS server is too busy to respond to the connect request from the WebLogic Proxy Plug-In.
This can be resolved by setting WLSocketTimeoutSecs to a higher value where the default value is 2. This allows the WebLogic Proxy Plug-In to wait longer for the connect request to be responded by the WLS server.

try adding below configuration in http.conf under the location tab of Virtual host:

DEBUG OFF
ConnectTimeoutSecs 50 (default is 10)
ConnectRetrySecs 5 (default is 2)
WLSocketTimeoutSecs 10 (default is 2)
WLIOTimeoutSecs 1800 (default is 300)
Idempotent OFF (default is ON)

In weblogic nodes

domain --> environment --> servers --> click on the required server --> tuning--> Accept Backlog:  --> default value is 300. Made it 375.
 
restart weblogic nodes and apache , this should fix your no resource issue.

Br

Punit