nmap showing lots of ports open that shouldn't be

[jim at datamantic.com (Jim Bassett)]

On Feb 12, 2006, at 4:56 PM, Steve Bergman wrote:

> Jim Bassett wrote:
>
>>
>> Is it over reacting to pull the plug and start over?
>
>
> Silly question.  You are certain that the machine you are probing  
> is your machine, right?  The ip address of you cable modem hasn't  
> changed without you knowing it, etc?  (I've done sillier things,  
> which is why I ask.)
>
> It's odd that smtp shows to be open, e.g.  Even without the  
> firewall, isn't sendmail configured only to listen on 127.0.0.1?
>
> -Steve

I've done sillier things in the past. But I am probing the right  
machine. It is colocated on a static IP. I just ran it again.

The machine I am using to run nmap is connected to the net through a  
friends base station and I don't know anything about his setup. But I  
can successfully surf, send mail, and ssh into my server. Is there  
any chance that even though I am specifying my server IP in nmap that  
it is instead scanning my friends machine on my local network?

About smtp: I did just install a mail server, so I guess that is why  
smtp is open. But I didn't explicitly open the port myself. I can see  
in netstat that a bunch of stuff is open for mail (and spam assassin  
and clamav.) Maybe that install messed with iptables?