How do you forward from static internal to dynamic external?

[Clark, Bill]

I am familar with routing and many comercial firewalls.  One problem
I can't get past in an environment where the ISP is giving IP info to
external 
interface via DHCP.  How do you forward from your internal interface to the 
external interface?  In order to do this I would have to set the external
interface
address as the default gateway for the internal.  But I can't do this since
I don't 
know what address the external interface is going to have.

The only solution I can come up with is to do add the default route
by hand after doing an ifconfig.  The problem with this is that everytime
I reboot I have to figure out the external IP.  Perhaps I could write a
script 
to capture and create the route.  But that isn't very elegant.  What if the
IP 
address expires on the interface and it receives a new one while up and
running
without a reboot.  This happens.

How are other people handling this problem?

Up until two days ago I didn't care.  I had my Sonicwall firewall, but now
it is fried and
I have to come with a cheap solution.  I can't keep shelling out $500
evertime my firewall
die's.  Assuming that this trend continues that would amount to $250 a year
plus the cable 
access fee.  Dial-up doesn't look so bad now  $12 a month.

bclark at astralpoint.com
bclark1 at kc.rr.com

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