I have a desktop machine onto which I installed woody, which originally
ran a 2.2.20 kernel and was configured using heimdall to use ipchains
for firewalling. (There is a script /etc/heimdall/firewall.sh which
invokes ipchains rules.) Awhile ago, I built a custom 2.4.18 kernel and
have been running that. This machine uses a dial-up connexion to connect
to my ISP, and I now want to allow access to the dial-up connexion via a
local network to a laptop that I have just acquired pre-installed with sarge.
In trying to figure out what I have to do get this to work, I tried running
ipchains -L on the desktop, and got the response:
ipchains: Incompatible with this kernel
(iptables is not installed, since I didn't want to screw up the 2.2.20
configuration.)
This is strange. Looking at the options I used in building the 2.4.18
kernel, I see that under "IP: Netfilter configuration", I specified both
IP tables and ipchains support as modules. Does this mean that since
changing to a 2.4 kernel that I lost firewalling? There don't seem to be
any error messages in the system log files relating to ipchains.