Re: Problems configuring gateway/firewall with static IP addresses - RESOLVED

[Matt Singerman <msingerman@xxxxxxxxxx>]

Hi all,

After sending my last email, I realized I was doing everything 
completely incorrectly and reconfigured the machine to act as a network 
bridge.  It took me about 20 minutes to set up and is working 
flawlessly.  Thanks for your help!

Matt Singerman wrote:
> Hi Ed,
>
> Wow...  This all seems, uh, complicated.  Maybe I am going about this 
> in the wrong way?  Our existing gateway machine definitely doesn't 
> have a configuration this complex, especially since I don't have any 
> control over 141.161.185.38.  What would be the best method to 
> firewall off just one part of a network - to have just a few servers 
> on 141.161.111.x behind a firewall, and all the other machines on that 
> same network not behind it?  Am I making things too complicated here?
>
> Ed Greshko wrote:
> > Ed Greshko wrote:
> >  
> > > I wrote....
> > >
> > >    
> > > > 1.  Assuming eth0 is the Internet facing interface you need to change
> > > > its IP address as well as its netmask.
> > > >
> > > > IPADDR=141.161.111.1
> > > > NETMASK=255.255.255.252
> > > > BROADCAST=141.161.111.3
> > > >       
> > > That was only an example.  The important thing is that the netmask 
> > > needs
> > > to be 255.255.255.252 which gives you only 4 IP address on that
> > > interface and of these only 2 are usable as the others are the network
> > > address and the broadcast address.
> > >
> > > You could have...
> > > IPADDR=141.161.111.242  for eth0
> > > IPADDR=141.161.111.241  for 141.161.185.38 interface
> > > Broadcast=141.161.111.243
> > > Network=141.161.111.240
> > >     
> >
> > Forgot to mention that in this case eth1 needs to be changed as well as
> > default gateways...but I think that was obvious.  However, I forget that
> > what is obvious to me may not be obvious to others so it is better to
> > mention it....even if it is an afterthought and increases traffic.  :-)
> >
> >
> >