Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I used nmap to scan all the ports in the hosts in a network by using the command:

$ nmap

What I found is that it showed the following in the result:

Nmap scan report for
Host is up (0.0039s latency).
Not shown: 998 closed ports
23/tcp open telnet
80/tcp filtered http

What does represent? Is it a specific interface or something else?

share|improve this question
What version of nmap did you use, and what exact command line? Is this the whole report? I don't recognize “scan report” in nmap output. Usually, an address ending in .0 in a /24 network is the network address and cannot be used for a machine, but it's technically possible to have a machine with this address. – Gilles Nov 12 '11 at 1:28
up vote 2 down vote accepted is the IP address of one of the hosts you scanned. If your network is actually (or larger), then 100.0 is a perfectly valid IP address. is part of the pre-CIDR Class B IP space, so you may have gotten a default network of if you didn't configure otherwise (and 100.0 completely valid on that network).

If you don't want to scan .0, you can invoke nmap with a range: nmap -sS

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.