The timeout specified has expired: ajp_ilink_receive() can't receive header

[Joe Hansen <joe.hansen.at@xxxxxxxxx>]

Hi All,


Randomly our website goes down and I see the following errors in the Apache Log files. When I googled for the error, though I did not find a definitive answer, I found forum posts where people think this could be caused due to connectiontimeout setting. I hate to experiment with settings on our website without knowing when and why this error occurs and how do I fix it. 

/* /etc/httpd/logs/error_log file */
[Fri Sep 28 15:26:43 2012] [error] (70007) The timeout specified has expired: ajp_ilink_receive() can't receive header
[Fri Sep 28 15:26:43 2012] [error] ajp_read_header: ajp_ilink_receive failed
[Fri Sep 28 15:26:43 2012] [error] (120006)APR does not understand this error code: proxy: read response failed from 127.0.0.1:8009 (localhost)

/* /etc/httpd/logs/ajp.error.log file */
[Fri Sep 28 15:27:25 2012] [error] ajp_read_header: ajp_ilink_receive failed
[Fri Sep 28 15:27:25 2012] [error] (120006)APR does not understand this error code: proxy: read response failed from (null) (localhost)

/* /etc/httpd/conf/extra/httpd-vhosts.conf file */
<VirtualHost *:80>
        .....
        ..... 
        <Proxy *>
                AddDefaultCharset Off
                Order deny,allow
                Allow from all
        </Proxy>

        ProxyPass / ajp://localhost:8009/
        ProxyPassReverse / ajp://localhost:8009/
</VirtualHost>


I can provide any additional details that you might need. Your help is greatly appreciated!

Thanks!
Joe

RedHat Enterprise Linux 6.3 (64-bit)
Apache 2.2.15-15 (64-bit) 
Tomcat 7 (64-bit)
mod_proxy_ajp
Java 1.6.0_35 (64-bit)