Very Computer

by **Patrick Heal** » Sat, 01 Dec 2001 15:08:39

Hello,

I have a Red Hat 7.1 distribution installed on a dual-NIC system. On one
side (the first NIC) is a DSL connection. On the other is the internal
network.

Can anyone direct me to a source that offers a cookbook approach to setting
up routing between the internal network and the DSL/Internet connection?
I've been beating my head against the wall on something that I thought I
knew how to do...

</embarrased>

Thanks,

Pat Healy

by **Jakob Strebe** » Sat, 01 Dec 2001 21:20:02

Patrick,
when you say dual NIC, do you mean 2 Etnernet cards?

Can you give some more details about your config?
what netstat -rn tells us?

jakob

>Hello,

><embarrased>

>I have a Red Hat 7.1 distribution installed on a dual-NIC system. On one
>side (the first NIC) is a DSL connection. On the other is the internal
>network.

>Can anyone direct me to a source that offers a cookbook approach to setting
>up routing between the internal network and the DSL/Internet connection?
>I've been beating my head against the wall on something that I thought I
>knew how to do...

></embarrased>

>Thanks,

>Pat Healy

by **Patrick Heal** » Sat, 01 Dec 2001 22:04:28

Yes, I mean 2 NICs (rather than a "multi-port" ethernet card...)

The NIC connected to the internal network is 192.168.0.X w/ a net mask of
255.255.255.0
The NIC connected to the outside world has a fixed IP address assigned by
the ISP. (For obvious
reasons I won't post that IP addres...).

I'm more interested in getting the Linux host to do very basic routing with
out NAT, and I'd like to take
advantage of the iproute2 package that comes with the 2.4 kernel.

Thanks Jakob!

Pat Healy

> Patrick,
> when you say dual NIC, do you mean 2 Etnernet cards?

> Can you give some more details about your config?
> what netstat -rn tells us?

> jakob

> >Hello,

> ><embarrased>

> >I have a Red Hat 7.1 distribution installed on a dual-NIC system. On one
> >side (the first NIC) is a DSL connection. On the other is the internal
> >network.

> >Can anyone direct me to a source that offers a cookbook approach to
setting
> >up routing between the internal network and the DSL/Internet connection?
> >I've been beating my head against the wall on something that I thought I
> >knew how to do...

> ></embarrased>

> >Thanks,

> >Pat Healy

by **Dean Thompso** » Sat, 01 Dec 2001 22:21:08

Hi!,

Quote:> <embarrased>

> I have a Red Hat 7.1 distribution installed on a dual-NIC system. On one
> side (the first NIC) is a DSL connection. On the other is the internal
> network.

> Can anyone direct me to a source that offers a cookbook approach to setting
> up routing between the internal network and the DSL/Internet connection?
> I've been beating my head against the wall on something that I thought I
> knew how to do...

Check to make sure that you have activated IP forwarding on your system (echo
"1" > /proc/sys/net/ipv4/ip_forward) or change the entry in the
/etc/sysctl.conf file. You will then need to activate your MASQ'ing
arrangements:

/sbin/iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
^^^^ ---> This is the interface that
is connected to your DSL
network equipment.

You may also have to make sure that you aren't running a restrictive firewall
on your system which would be blocking the return on the incoming MASQ'ed
packets. RH 7.1 and 7.2 by default will install a pretty restrictive
firewall.

See ya

Dean Thompson

by **Dean Thompso** » Sat, 01 Dec 2001 22:42:10

Hi!,

Quote:> Yes, I mean 2 NICs (rather than a "multi-port" ethernet card...)

> The NIC connected to the internal network is 192.168.0.X w/ a net mask of
> 255.255.255.0
> The NIC connected to the outside world has a fixed IP address assigned by
> the ISP. (For obvious
> reasons I won't post that IP addres...).

> I'm more interested in getting the Linux host to do very basic routing with
> out NAT, and I'd like to take advantage of the iproute2 package that comes
> with the 2.4 kernel.

If you want your internal network to talk to the outside world, won't you have
to use NAT to allow the packets in and out of your system ?

See ya

Dean Thompson

by **Karl Heye** » Sat, 01 Dec 2001 22:55:33

> Yes, I mean 2 NICs (rather than a "multi-port" ethernet card...)

> The NIC connected to the internal network is 192.168.0.X w/ a net mask of
> 255.255.255.0
> The NIC connected to the outside world has a fixed IP address assigned by
> the ISP. (For obvious
> reasons I won't post that IP addres...).

> I'm more interested in getting the Linux host to do very basic routing with
> out NAT, and I'd like to take
> advantage of the iproute2 package that comes with the 2.4 kernel.

direct routing is not going to be possible without NAT with addresses
like 192.168 are involved. If you don't want NAT involved then you
have to use a proxy.

karl.

by **M. Buchenriede** » Sun, 02 Dec 2001 05:28:32

>Yes, I mean 2 NICs (rather than a "multi-port" ethernet card...)
>The NIC connected to the internal network is 192.168.0.X w/ a net mask of
>255.255.255.0
>The NIC connected to the outside world has a fixed IP address assigned by
>the ISP. (For obvious
>reasons I won't post that IP addres...).

Why? It won't hurt.

Quote:>I'm more interested in getting the Linux host to do very basic
>routing with
>out NAT,

[..]

Impossible with a 192.168.0.x network address. Packets originating
from within that network have to be masqueraded prior to being sent
through a router into the Internet.

Otherwise, if all you'd need was Internet, setup a proxy.

Michael
--

Lumber Cartel Unit #456 (TINLC) & Official Netscum
Note: If you want me to send you email, don't munge your address.

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Basic routing help

Basic routing help

Basic routing help

Basic routing help

Basic routing help

Basic routing help

Basic routing help

Basic routing help