If you use apache to forward request to a local running tomcat, you may encounter this error message in the error.log:
[error] (13)Permission denied: proxy: HTTP: attempt to connect to 127.0.0.1:8080 (*) failed
If you have SELinux running you have to check if it allows local connections, by running:
getsebool -a | grep httpd
you have to check that the following is written:
httpd_can_network_connect –> on
if it is off, you have to enable it:
setsebool -P httpd_can_network_connect=1
and restart your apache.
This tip has been taken from: http://swapyourbooks.com/welcome/knowledgebase/misc/selinux-allow-httpd-tomcat-proxy.html