Secrete of NMAP:How to use Nmap(Network Mapper)
Nmap is incredible tool. It is completely free open source utility. Today i am showing inside my post “ secrate of Nmap/How to use Nmap” installation and configuration of NMAP and how to use NMAP into System. Nmap is used to map your network and find out network problem like connectivity problem, find out your target information, Operating System information, checking live system and open ports and what services are running into system. You can scan large network by help of nmap with in sort time.
How to Install nmap into your Linux System?
1) Download nmap rpm or source code
Install nmap by RPM.
Installation by help of rpm is so simple. Only download rpm package or execute siple rpm related commands.
#rpm –ivh nmap-*
If your task are successfully complete then check your nmap are install or find out it information.
#rpm –qi nmap
If here show nmap related information like nmap version, nmap size, nmap developer organization name and etc. then your installation is successfully complete. Now you can execute nmap related commands
Install nmap by of source code
First decompress your nmap source bundle. Execute given command.
#tar –xvf nmap-*
Now time to installation
#cd nmap*
#./configure
#make || gmake
#gmake install
Note:- if your namp installation directory is /usr/local/bin. It’s very danger because any local user can use your namp utility. I suggest you always install nmap into pacific directory or set permission on it or use /sbin directory.
How to use Nmap commands.
Note:-Check information about spacific IP address, by default Nmap only search 1000 ports.
#nmap 192.168.10.2 – Here you can put any IP address. Which you want?
OR
#nmap s1.techlazy.com
#nmap –v s1.techlazy.com
1) Scan complete specific subnet.
#nmap 192.168.10.0-255
OR
#nmap 192.168.10.0/24
2) Send packet to complete subnet and return all reachable system.
#nmap –sp 192.168.10.* – any specific subnet
3) Fast scan specific address.
#nmap -Ts 192.168.10.1-50
4) Scan only TCP port , and specific port address.
#nmap –sT –p 80 192.168.10.0/24
5) Scan only UDP Ports.
#nmap –sU 192.168.10.2
6) Scan only top 50 ports.
#nmap –top-ports 50 192.168.10.0/24
7) Only scan related to ping. If you don’t have admin or root level privileges. You can run it commads.
#nmap –sP 192.168.10.0/24
Attributes of nmap command
I will describe nmap more commands into another nmap tutorials. Now I am showing some common useful attributes or option. Which are mostly uses into scan.
-sT – TCP Scan
-sS – SYN Scan (Synchronization scan)
-sF – FIN Scan
-sX – Xmas Scan
-sN – Null Scan
-sP – Ping Scan
-sU – UDP Scan
-sW – Windows Scan.
How to save output any specific commands and check result.
#nmap 192.168.10/20 > techlazy.com OR
#nmap –oN /home/arif/techlazy 192.168.10.2 OR
#nmap –oN techlazy 192.168.10.2
