Strange Httpd Problem

Home » CentOS » Strange Httpd Problem
CentOS 1 Comment


I’m currently setting up an IP accouting machine using CentOS 6 and pmacct, compiled from source. The machine has two network interfaces :
– a “normal” one, used for SSH remote administration and viewing the accouting data through a webserver (eth0)
– a “monitor” one, plugged into a mirroring port of our switch and with no IP address defined (eth1)

The accouting part works fine, but I’m getting problems with the webserver. To ensure there are no interference with the monitor interface, I set iptables to drop all the outbound traffic on eth1 and httpd in bound to the IP address of eth0, but I randomly become unable to contact the webserver;
my browser tells me it couldn’t contact it. The SSH access works fine and the CPU and memory usage are OK (5% CPU and 10% memory, our network is currently on low traffic).

Any clues why this is happening ?

Regards, Eric Viseur

One thought on - Strange Httpd Problem

  • Not off hand, but you could help by posting the configuration file containing your rules instead of a vague description of it. There’s not really enough to go on yet.

    Rules dropping outbound traffic on the un-numbered interface are extraneous. If the kernel doesn’t have an address on that interface, it won’t have any routes assigned to that interface either. Hence, no traffic will be directed out of the un-numbered interface. If you list your rules with “iptables -L -v” you’ll see the packet counter on that rule has 0 hits, because it’s never used.