two problems and a question with nmap or nmapwin

["Robert Thompson" <rat () shorelinebf com>]

I downloaded and installed nmap win, and have two problems and a question.
 
Problem 1
 
Things were working fine (except for problem 2 below) until I installed winpcap 2.3.  From that point forward 
everything I tried to do with nmapwin seemed to take forever.  I would fire up a command and it will just sit there, 
forever, till it comes back.  Quick scans of a range of addresses that would take only a few seconds will now run for 
minutes at a time for EACH address in a range of addresses.  Honestly, it doesn't matter what options I choose and what 
selections I make - it takes FOREVER to finish.  Makes no difference if I do it through nmapwin or nmap from a command 
line.  It CRAWLS!  For example, here is the screenshot back from a nmap commandline run:
 
nmap -sT -P0 -F -T 3 172.16.0.15
 
Starting nmap V. 3.00 ( www.insecure.org/nmap )
Interesting ports on DEV-1.shorelinebf.com (172.16.0.15):
(The 1146 ports scanned but not shown below are in state: closed)
Port State Service
135/tcp open loc-srv 
139/tcp open netbios-ssn 
445/tcp open microsoft-ds 
12345/tcp open NetBus 
Nmap run completed -- 1 IP address (1 host up) scanned in 230 seconds
 
Taking 233 seconds to scan one port (it's actually the machine nmap is running on) means that scanning a range of 255 
machines might take as long as 17 hours to finish.  I swear I did the same command before installing winpcap2.3 and it 
took less than 1 minute to do 255 addresses.  Any ideas?
 
Problem 2
 
If I enter a range option of /16 to scan, for example, 192.168.0.0 through 192.168.255.255, the system nmap is running 
on reboots itself!  An option of /24 is okay, but /16 and I get a reboot.  And a chance to decide whether or not to run 
chkdsk, since it's the kind of shutdown that W2K thinks is very unkind.  Any ideas?  (This was happening BEFORE I 
installed winpcap).
 
Question:
 
My reason for getting nmap is because I want to find every IP address that is connected to my network.  Most of them I 
know are out there, but I do not know if there are any "rogue" hardware out there that is either hooked up by someone 
else or is a piece of gear that should be there that I have overlooked.
 
I want an nmap command that will give me back a list of all of the IP addresses on this side of my firewall so that I 
can know that I have all of them in my network diagram.
 
What is the nmap command I want to use to get this kind of information back?
 
Any help with any of these problems greatly appreciated.
 
Thanks,
 
-bob thompson-
-shoreline solutions-
bob () shorelinebf com
rat () shorelinebf com