Hi,
Firstly, sorry if this has been asked before, but it seemed a bit too "general" to search for...

I have just installed RH9 on a Dell 6100/200 Server, in which I have 2 NICs (one 10-baseT and a 10/100).

When starting the Server, and pinging it from another machine, it will respond briefly from one of the NICs, then stop responding (the second NIC does not respond at all - even though the system brings them both up successfully). (Obviously some kind of firewall/security rule being implemented when it stops responding). Question is, which one?

I've set the security defaults to "no firewall" (my router can handle that for the time being), and have setup the 2 NICs with IP addresses local to the network, but I cannot reach the Server, nor can the server ping anything on the network; even the gateway! (Server's NIC addresses are 192.168.1.2 and 192.168.1.3, with the gateway on 192.168.1.1).

I ran a LAN traffic analyser on the Server, and could actually see the TCP/ICMP traffic generated when another machine was pinging it, but it still won't answer or connect to anything else...

What the hell am I doing wrong?

Can you post the output from:
iptables -nL

Hi David. I had a quick look before coming to work; there actually doesn't appear to be any actual configured entries for allow_hosts, deny_hosts etc. This surprises me, as I' d have thought (naively , probably) that editing/changing security/lokkit settings would have added "allow_all" or "Deny_none" type settings...I'll continue searching around for a sample (working) iptables config I can modify for my purposes and/or post mine up later today.

A firewall rule would apply full-time, not allow traffic for a while then come into effect. Same would be true of a hosts.deny problem.
Does ifconfig show packets dropped or mangled?

Good point, but I'm thinking that (upon boot) that the NIC/s are being enabled (ie. starting eth0/1) when I get a few ping returns, then the firewall rules are being applied (whereupon the ping responses stop).

I'll do a bit of stuffing around with the iptables tomorrow...then let people know how I went. Thanks for looking/replying to the post, BTW .