Re: [vox-tech] Firewall

[jdnewmil@dcnMAPS.davis.ca.us]

On Wed, 10 Jan 2001, Jay wrote:

> I'm trying to decide how to setup my next firewall.  I see smoothwall
> (which I hear is pretty good) uses only 2 nics (internal and external)
> and port forwards request to machines on the private internal network.

Two nics is pretty much a minimum for a firewall. :)

> Then others use that External/DMZ/Internal setup (like in the ipchains howto).
> 
> Why would I choose one over the other?

Paranoia.  If you allow ANY services to portforward in and there is a
security flaw in the server daemon(s), then once your box is cracked
your whole network is compromised.  If you have three NICs, or better yet,
a second firewall, then your private lan can access the server, and the
outside world can access it, but if the server is cracked then they are
faced with getting through a firewall that contains no holes.  The
headache with this is that your server is pretty thoroughly isolated from
your LAN, so YOU can't schedule actions to push data into your lan... all
data movement to or from your LAN must be initiated from within the lan.  
Thus, if you have a database you want to serve data from it must be in the
demilitarized zone on or with the other servers.

Most people don't want to setup dedicated servers in their homes with
limited communication among the rest of their network, just because
someone _might_ be able to crack their system.

> Also, isn't there some way to setup a firewall that doesn't have hard
> drive and boots off the floppy.

http://www.linuxrouter.org  (barebones, but simple)
http://lrp.c0wz.com  (clearing house of information about LRP)
       (Steinkuehler's preconfigured images can make initial
       setup very easy.... _if_ he has one that matches your needs.
       Rather complex if you start adapting it to different setup.
       Douthitt's Oxygen is tuned for experienced *nixers.)

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