Redhat 8.0 Firewall

I'm trying to use IP Masquradeing to connect an older computer to Redhat 8.0. I haven't been able to allow it to connect.

I've noticed that if I attempt to change the security level it doesn't seem to work.

It's usually set to High.

I try to change it to Medium and allow different incoming connections.

I save it, but when I go back to it later, it's set back to High.

Anyone have any ideas on this?

For RedHat, the output of
/etc/rc.d/init.d/iptables status
--or--
/etc/rc.d/init.d/ipchains status
would be helpful here. It will display all your firewall rules, and hopefully someone will be able to answer your questions.

The GUI for Firewall Settings just doesn't make any sense to me. Just like you said, it seems that when you make a change and then go back nothing changes. Just use the commands that bentz said to see your current firewall rules or do:

iptables -L

I'm not at all familiar with the GUI tools... But: If you make rule changes, you will need to save them so that they survive a reboot. Use the command 'iptables-save > /etc/sysconfig/iptables'. This will write your current ruleset to a configuration file, which will be read upon the next reboot or '/etc/rc.d/init.d/iptables start'. There is also an iptables-restore, but I'm too lazy to RTFM for that one.

Get Guarddog. I did, works wonderfully.

http://freshmeat.net/projects/guarddog/

I'll give these a try. Thanks for your help.

I ran iptables status and here's what I got:

Table: nat
Chain PREROUTING (policy ACCEPT)
target prot opt source destination

Chain POSTROUTING (policy ACCEPT)
target prot opt source destination
MASQUERADE all -- anywhere anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Table: filter
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABL
ISHED
ACCEPT all -- anywhere anywhere
LOG all -- anywhere anywhere LOG level warning

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain RH-Lokkit-0-50-INPUT (0 references)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:http flags:S
YN,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:ftp flags:SY
N,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh flags:SY
N,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp flags:S
YN,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:telnet flags
:SYN,RST,ACK/SYN
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT udp -- ns02.toresd01.pa.comcast.net anywhere udp spt:dom
ain
ACCEPT udp -- ns01.toresd01.pa.comcast.net anywhere udp spt:dom
ain
REJECT tcp -- anywhere anywhere tcp flags:SYN,RST,AC
K/SYN reject-with icmp-port-unreachable
REJECT udp -- anywhere anywhere udp reject-with icmp
-port-unreachable

I'm not sure if everything is alright here.