[ale] Networking weirdness

[Jim Popovitch]

So, I've got a temporary strange system setup at home.  Basically there 
is the existing cable modem + wifi-enabled linksys router that runs the 
everyday stuff including a printer with the IP address 192.168.3.2.  The 
printer is mostly powered off due to lack of use.  Lately I've been 
testing/config'n some new hardware and it is now setup with new public 
IPs.  In order to have network connectivity I have them hooked up to a 
second linksys router which acts as a wan gateway.  The inside address 
space, of the second router, is 69.61.x.128/25, while the "wan" side IP 
is 192.168.3.2, the same as the printer (don't ask why, it was a late 
night that night).   Here's the layout:

      CableModem (192.168.100.1)
           -> Wifi/Router (192.168.3.0/28)
                  ->  Home computers/laptop (192.168.3.3-10)
                  ->  HP Printer (192.168.3.2)
                  ->  SecondRouter (192.168.3.2)
                          -> NewBoxA (69.61.x.131)
                          -> NewBoxB (69.61.x.132)
                          -> NewBoxC (69.61.x.133)

Wifi/Router has a static route for 69.61.x.128/25 that points to 
192.168.3.2.

I've been working on NewBoxA/B/C from my laptop (.5) and needed to print 
something.  So, I went into the other room and powered on the printer 
and then came back and successfully printed what I needed.  The whole 
time ssh sessions to NewBoxA and NewBoxB remained active and open (with 
stress& and top running in each) even though the gateway device to them 
shares the same IP as the printer.  Additionally NewBoxC was continuing 
to rsync from a remote host over the Internet.

It's worth pointing out that the http admin interface to SecondRouter 
(192.168.3.2:8080) was not available while the printer was powered on, 
but the printer (HP) admin interface on port 80 was.  As soon as the 
printer was powered back off the admin interface for SecondRouter could 
be reached immediately.

What I find amazing is that arp caches seemed to change, possibly 
because the printer came online.  But once the printer was powered off I 
would have thought that my laptop (winXP) would still use it's arp cache 
for the printer instead of re-locating SecondRouter.

-Jim P.