RE: 2 NIC cards not talking

Ray Olszewski
2004-01-22T01:35:28Z

At 07:32 PM 1/21/2004 -0500, Chadha, Devesh wrote:
>Well my reason for not giving is that it is a public IP and does not have
>any firewalls in place. This exposes my server much more to unauthorized
>"visit"
>
>Anyway...lets get down to getting this done.
>
>I am on RH Linux 8
>uname -a is Linux 2.4.18
>netstat -nr gives
>192.168.1.0 0.0.0.0 255.255.255.0 U
>eth1
>xxx.xxx.xxx.0 0.0.0.0 255.255.255.0 U eth0
>127.0.0.1 0.0.0.0 255.0.0.0
>U lo
>0.0.0.0 xxx.xxx.xxx.1 0.0.0.0 UG eth0
>
>ifconfig gives me that eth0, eth1 and lo are correctly configured.
>
>ip_forward gives a "1"
>
>What do the gurus say???

Not being a guru -- I'm just a guy who knows something about routing and
firewalling -- I need the answers to ALL of the questions I asked, not just
the less than 2 of them that the information above answers.

That includes the two questions I ask below about your public IP address.

It includes examples of the tests you did and how they failed; see my prior
message for the details.

And just to be clear -- can this host *itself* not connect to other hosts
on the Internet, or is the problem ONLY with LAN hosts attempting to use it
as a NAT'ing router?

The kernel capability that firewalls -- iptables in the case of 2.4.x
kernels - is the same capability that NATs. It certainly seems that you
need to NAT this connection (or if not, your setup with your ISP is
suficiently unusual that you won't get meaningful help without describing
it). So if you do "not have any firewalls in place", how *is* the system
NAT'ing LAN hosts?

In addition to everything I asked for before, we probably need to see the
output of

iptables -nvL

>-----Original Message-----
>From: Ray Olszewski [mailto:ray@comarre.com]
>Sent: Wednesday, January 21, 2004 7:02 PM
>To: linux-newbie@vger.kernel.org
>Subject: RE: 2 NIC cards not talking
>
>
>At 04:52 PM 1/21/2004 -0500, Chadha, Devesh wrote:
> >[...]
> >Ray:
> >I have static IP and therefore I cannot give the actual IP address.
>
>I don't understand why, unless for some reason you think that your IP
>address is a secret. Once you start using the address for any purpose, it
>will be known to everyone you deal with, after all.
>
>Even if you are that secretive, we do need to know a couple of things about
>the address. One, is it a public IP address? Two, is it on a different
>network (probably what you call a "subnet") from the internal, LAN
>interface? If we don't know at least that much information reliably, then
>we won't be able to eliminate, or spot, some possible sources of your
>problem.
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