nmap

OS DETECTION

 -O: Enable OS detection
 --osscan-limit: Limit OS detection to promising targets
 --osscan-guess: Guess OS more aggressively

nmap -O jump221
 
Starting Nmap 5.21 ( http://nmap.org ) at 2011-12-27 12:34 CST
Nmap scan report for jump221 (161.89.145.221)
Host is up (0.023s latency).
Not shown: 995 closed ports
PORT     STATE SERVICE
21/tcp   open  ftp
22/tcp   open  ssh
80/tcp   open  http
111/tcp  open  rpcbind
3306/tcp open  mysql
Device type: general purpose
Running: Linux 2.6.X
OS details: Linux 2.6.18 (CentOS 5.1, x86)
Network Distance: 6 hops
 
OS detection performed. Please report any incorrect results at http://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 8.44 seconds

• nmap -A -T4 scanme.nmap.org

The only Nmap arguments used in this example are -A, to enable OS and version detection, script scanning, and traceroute; -T4 for faster execution; and then the two target hostnames.

Multiple address

$ nmap 161.89.145.220-221
 
Starting Nmap 5.21 ( http://nmap.org ) at 2011-12-27 12:29 CST
Nmap scan report for jump220 (161.89.145.220)
Host is up (0.024s latency).
Not shown: 985 closed ports
PORT     STATE SERVICE
22/tcp   open  ssh
23/tcp   open  telnet
135/tcp  open  msrpc
139/tcp  open  netbios-ssn
445/tcp  open  microsoft-ds
1025/tcp open  NFS-or-IIS
1033/tcp open  netinfo
1039/tcp open  unknown
2301/tcp open  compaqdiag
2381/tcp open  unknown
3389/tcp open  ms-term-serv
5555/tcp open  freeciv
5800/tcp open  vnc-http
5900/tcp open  vnc
8081/tcp open  blackice-icecap
 
Nmap scan report for jump221 (161.89.145.221)
Host is up (0.025s latency).
Not shown: 995 closed ports
PORT     STATE SERVICE
21/tcp   open  ftp
22/tcp   open  ssh
80/tcp   open  http
111/tcp  open  rpcbind
3306/tcp open  mysql
 
Nmap done: 2 IP addresses (2 hosts up) scanned in 7.87 seconds