[NTLUG:Discuss] pass all packets between two nics

[severian@pobox.com]

Howdy,
   I set up a SuSE 8.2 box that will be a VPN server, I hope.  I want to 
prove to myself that having this box in the path between their internet 
connection and the rest of the office will not cause any problems.  I think 
I should start by connecting one nic to the Cisco router and the second nic 
to the office switch that the router currently goes to.  I need to have my 
new machine pass everyhing between the two nics.  This leads me to several 
questions.
   1.  Is there a name for what I want the computer to do with the two 
nics?  I ask because I have been searching for details on how to do this 
without success.  If there is some term I should search on, maybe my luck 
would be better.
   2. I was going to start by leaving ethereal running for a few days 
monitoring one of the nics.  From reading the ethereal manual, I see this 
is not the normal way people run ethereal.  The manual suggests plugging 
the monitored nic into a hub(not a switch) that carries traffic you want to 
monitor and I can see why this is the normal case.  My machine will need to 
be in the middle to unencrypt and pass traffic to the internal network from 
the insecure internet.  Is there a problem with what I propose?
   3.  SuSE does not include the autologin package.  Is this just because 
it is nrmally a security risk or is there something odd abut SuSE that 
causes problems for autologin?  In the case of power failures, I need to 
have this machine restart so the customer can still use the net.
Your comments will be welcomed,
Ralph