Hello all. I have a routing problem.
I have a linux machine (OpenSuSE) that acts as a gateway for the LAN and
is connected to internet using two different internet providers.
I want to ping this linux machine from the lan and from outside, using
both public ip (even from the lan, I have to call linux using external
public ip and not the internal lan ip).

Let's call:
$IP1 = linux ip on first provider's net
$P1_NET = first provider's net
$P1 = default gateway ip on first provider's net
$IF1 = ethernet interface wired with first provider's net

I have tried these commands:
ip route add $P1_NET dev $IF1 src $IP1 table 1
ip route add default via $P1 table 1
ip route add $P2_NET dev $IF2 src $IP2 table 2
ip route add default via $P2 table 2
ip route del default
ip route add default via $P1
ip rule add from $IP1 table 1
ip rule add from $IP2 table 2

Now, if I ping $IP1 or ping $IP2 I get correct answer from outside but
not from the LAN.

If I substitute the 7th line with this line:
ip rule add from $IP1 to 82.0.0.0/8 lookup 2

than ping works from LAN and from outside but obviously it works only
from external ip like 82.a.b.c.
Extending this for all valid addresses I would have to write a lot of rules:
ip rule add from $IP1 to 1.0.0.0/8 lookup 2
ip rule add from $IP1 to 2.0.0.0/8 lookup 2
ip rule add from $IP1 to 3.0.0.0/8 lookup 2
....
excluding 192.168.0.0/16, and than the same for $IP2. It seems me not
very good. :-)

Have you got any suggestion to solve the problem?
Thank you very much.

On Tue, 22 Jul 2008 14:44:01 +0200, Alessandro Topo Galileo typed this
message:

> Hello all. I have a routing problem.
> I have a linux machine (OpenSuSE) that acts as a gateway for the LAN and
> is connected to internet using two different internet providers. I want
> to ping this linux machine from the lan and from outside, using both
> public ip (even from the lan, I have to call linux using external public
> ip and not the internal lan ip).
>
> Let's call:
> $IP1 = linux ip on first provider's net $P1_NET = first provider's net
> $P1 = default gateway ip on first provider's net $IF1 = ethernet
> interface wired with first provider's net
>
> I have tried these commands:
> ip route add $P1_NET dev $IF1 src $IP1 table 1 ip route add default via
> $P1 table 1
> ip route add $P2_NET dev $IF2 src $IP2 table 2 ip route add default via
> $P2 table 2
> ip route del default
> ip route add default via $P1
> ip rule add from $IP1 table 1
> ip rule add from $IP2 table 2
>
> Now, if I ping $IP1 or ping $IP2 I get correct answer from outside but
> not from the LAN.
>
> If I substitute the 7th line with this line: ip rule add from $IP1 to
> 82.0.0.0/8 lookup 2
>
> than ping works from LAN and from outside but obviously it works only
> from external ip like 82.a.b.c.
> Extending this for all valid addresses I would have to write a lot of
> rules: ip rule add from $IP1 to 1.0.0.0/8 lookup 2 ip rule add from $IP1
> to 2.0.0.0/8 lookup 2 ip rule add from $IP1 to 3.0.0.0/8 lookup 2 ...
> excluding 192.168.0.0/16, and than the same for $IP2. It seems me not
> very good. :-)
>
> Have you got any suggestion to solve the problem? Thank you very much.

Going on a limb here but wouldn't this be something better defined in
your /etc/hosts table.

/etc/hosts on remote machine.

$IP1 Linuxbox1_on.external.network

or
$P1_NET Linuxbox1_on.external.network


192.168.0.2 Linuxbox1_on.internal.network

Il 22/07/2008 20.58, noi ance ha scritto:

> Going on a limb here but wouldn't this be something better defined in
> your /etc/hosts table.
>
> /etc/hosts on remote machine.

This does not solve the problem, anyway thank you for your answer.
At last, it works (for interested people: comp.os.linux.networking,
thread with the same name).