On Monday 30 September 2002 07:27, Ingo Doerrie wrote:
Hello!
<snip>
Only one system can reach the Internet that functions as standard-gateway for all other systems, running some Virus-Scanner on windows NT 4.x.
Directly on its console internet works pretty fine but every packages sent to it from the LAN don't go through.
The only message shown on the LX-gateway is: "KERNEL:... martian source ..." from the IP-adress pointing to the LAN from the virus scanner system.
What does this martian source stuff mean and where does it come from?
Martians are packets that shouldn't exist. If, for example, you get RFC1918 traffic coming in from the outside world, that's Martian traffic (as most network admins configure routers to stop private-network traffic escaping - external traffic goes through a NAT gateway). Since incoming Martians *could* also be hostile, it's usually a good idea to block them; and firewalls tend to do so. If you're getting Martian-blocks from LAN traffic to your gateway, I'd have to wonder if you've got your internal and external interfaces mixed up. If not, have you enabled IP masquerading (NAT) on the firewall? - because the gateway is seeing your LAN traffic either as *external* traffic (and thus blocking it as Martian), or as private-network traffic (and thus not forwarding it). Hope this helps. Gideon Hallett.