Nmap, Firewall Testing, Idlescan?

[<j_goodman00 () yahoo co uk>]

Hi,

I have a couple of routers at various sites which include firewalls & I would like to use nmap to test them.

I have been experimenting with idlescans in an attempt to fool the firewall, but have been unsuccessful & am unsure if 
this is the firewall working, or me failing! :)

I am attempting to 'bounce' the scans off another computer of mine on a different connection:

e.g.
MyIP is 1.2.3.1
BounceIP is 1.2.4.1
TargetIP is 1.2.5.1
nmap -T5 -v -P0 -sI 1.2.4.1 1.2.5.1

When I look at the firewall logs they show logs along the lines of the following:
Source 1.2.3.1 Destination:1.2.5.1

Does this mean the firewall is working & successfully filtering the spoofed IP packets, or am I doing something wrong?


Cheers,

James