I am using a LAMP configuration. If I access the server at a very fast rate then sometimes I get 403 Forbidden as response. It is random, sometimes I get the response back and sometimes 403. I had in my iptables a rule which would prevent from flooding attack iptables -A INPUT -p tcp --syn -m limit --limit 5/s -i eth0 -j ACCEPT, I have removed this rule but the problem still persists. Looks to me that it is an apache issue. Please point me in the right direction.
iptables shouldn't cause a 403 HTTP error response, the connection will either be refused or dropped.
First place to look will be (typically) /var/log/apache2/error.log however this can vary across systems. locate error.log and locate httpd.log might point you in the direction of the logs at least -- do feel free to update the question with more information, but at the moment there isn't enough to go on to diagnose the issue.
