iptables slows down access to httpd server

[Steve Lindemann]

This, strictly speaking, isn't a Fedora problem, but I'm hoping someone 
out there can help.

system config:
dell poweredge 2950
kernel: 2.6.22.9-61.fc6
apache: 2.2.6

problem summary:  when iptables is turned on, web pages (graphics in 
particular) served up from the box are *extremely* slow to load, 
sometimes timing out.  when iptables is turned off, web pages served up 
from the box load normally.  I've compared my /etc/sysconfig/iptables 
file to another (fc6) server and they are effectively the same, *but* 
I've never had a problem with page loads from the other box.

I'm assuming (yes, I know 8^) that the problem lies with iptables, but 
I'm running out of places to look for answers.  Should I be looking 
somewhere other than the firewall?  Has anyone else seen this?  I'd 
really appreciate any help anyone out there could give.

((beware of line wrapping))
# Firewall configuration written by system-config-securitylevel
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:RH-Firewall-1-INPUT - [0:0]
-A INPUT -j RH-Firewall-1-INPUT
-A FORWARD -j RH-Firewall-1-INPUT
-A RH-Firewall-1-INPUT -i lo -j ACCEPT
-A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT
-A RH-Firewall-1-INPUT -p 50 -j ACCEPT
-A RH-Firewall-1-INPUT -p 51 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j 
ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j 
ACCEPT
-A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited
COMMIT

...ok I did manually edit the file to add the http rule, but up until 
now I've not had any problems doing that sort of thing.  Iptables does 
drive me just a bit crazy, but I do know enough to to that successfully 
(up until now that is).  Help!  ...and thanks!
--
Steve Lindemann                         __
Network Administrator                  //\\  ASCII Ribbon Campaign
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email: mailto:steve at marmot.org
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