Re: routing

["Adam Williams" <awilliam@xxxxxxxxxxxxx>]

On Jan 27,  1:44pm, Jason Kushmaul wrote:
> Subject: routing
> Hello all,
>
>
> My friends and I are trying to set up one of our boxes in our play lan to
> be a router and I want to learn how to set my linux box up as the router,
> rather than their Win95/98/nt boxes. <I'm greedy like that>
> we are using a v. 90 56k dial up connection with one account.
> We have reserved IP's for our lan, all set up on the other end (having
> friends in higher places is great:)  I know that this is called IP packet
> forwarding... thats it. heh.
> we are going to be using the linux box as the router, and win 95/98/nt
> boxes will be using the internet through it...
>
> some questions also.  What is the difference between IP masquerading, and
> IP packet forwarding?
> are they the same?  apples and oranges?
>
> any helpful explanations?  need more info?
>

IP masq is NOT the same as forwarding.  Forwarding is easier and more straight
forward.  You simply assign one of the IP address's given to you to all the
hosts on YOUR network,  I'm assuming that means all the ethernet interfaces.
 Then let your ISP assign the address to your dial-up interface when you
connect.
Set the Linux box as the default gateway on all the machines on your network,
 and enable forwarding on the Linux box by setting FORWARD_IPV4=true in
/etc/sysconfig/network.  That will make forwarding on by default when Linux
boots up.  But, for that sake of Linux appreciation, DO NOT REBOOT the Linux
box at this point.  Do a "echo "1" > /proc/sys/net/ipv4/ip_forward" to make the
change WITHOUT taking the machine down (do that with NT)!  Once you have done
all that you should be forwarding.

Next you should look into demand dial and firewalling.  The first for
convenience the second for security.  Win95/98 machines are sitting ducks for
network attacks.