Hi all, new member here. Is this the proper place to ask questions about
IPchains? If not I am sorry, can someone point me to a better place? Is
there an IPchains list?

I am running IPchains on RedHat 7.0 on a mediaone cable connection using
DHCP.
Q1: I used the Ziegler book but didn't really understand how to insure
that the firewall gets restarted if the IP changes (which happens very
infrequently) does anyone know of a how-to or other document that
discusses using Ipchains with DHCP?

Q2: After setting up the firewall, I became inundated with broadcast
messages in the log, getting a new one every few seconds. I take it this
is the nature of a shared DHCP cable modem network. What I want to do is
NOT log all of the broadcast messages. So I added rules to accept
traffic from the DHCP server addressed to my machine or a broadcast and
reject all others.

## Accept broadcast from the DHCP server 255.255.255.255
ipchains -A input -i $EXTERNAL_INTERFACE -p udp -s $DHCP_SERVER -d
$BROADCAST_DEST -j ACCEPT
## Accept broadcast from the DHCP server (24.255.255.255)
ipchains -A input -i $EXTERNAL_INTERFACE -p udp -s $DHCP_SERVER -d
$BROADCAST_DEST_2 -j ACCEPT
## I saw a packet from the DHCP server denied so I added this
(24.128.1.34 is the DHCP server)
ipchains -A input -i $EXTERNAL_INTERFACE -p udp -s 24.128.1.34 -d
$IPADDR -j ACCEPT

## discard the rest of the broadcast messages as garbage. Is it right to
do this or am I going to miss something???
ipchains -A input -i $EXTERNAL_INTERFACE -p udp -s $ANYWHERE -d
$BROADCAST_DEST -j DENY
ipchains -A input -i $EXTERNAL_INTERFACE -p udp -s $ANYWHERE -d
$BROADCAST_DEST_2 -j DENY   

I am wondering if I am doing this right, I am worried that I will block
something I need. Does the DHCP server ever change? Does anyone have 
better rules for a DHCP setup that will allow me to not log all of the
garbage but still receive any DHCP stuff I need?

Thanks,
Joe Junkin
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