[NTLUG:Discuss] disappearing default route

[jeremyb@univista.com]

  hey folks,
  I have a REdHAt 7.1 i386 machine on a LAN with the following simple route
table.

Destination     Gateway         Genmask         Flags   MSS Window  irtt
Iface
192.168.1.0     0.0.0.0         255.255.255.0   U        40 0          0
eth0
127.0.0.0       0.0.0.0         255.0.0.0       U        40 0          0 lo
0.0.0.0         192.168.1.1     0.0.0.0         UG       40 0          0
eth0

   up until last night it had a static IP of 192.168.1.3 and was completely
behind my linksys router.
  I changed eth0 to use DHCP last night using netconfig AND placed the
machine in the
linksys "DMZ" using the "DMZ port" on the router.  Everything seemed to work
fine until about 10 minutes ago when I suddenly had had no available
internet connection.
It wasn't too hard to figure out the problem was no default route.  
yes,  I said no default route....  it was there before and haven't been
monkeying with 
the table or the NIC.  My QUESTION IS, why might it disappear like that?
I added it back without issue.


-Jeremy