We will begin network admin package 2 , Check the first package here :
Agenda for this package :
- $$ netstat
- $$ ifstat
- $$ tcpdump
- $$ dhclient
- $$ nmap
- $$ telnet
- $$ ssh
- $$ minicom
- $$ ftp
- $$ wget
- $$ showmount
1- netstat
- ** Function : used to display network connections , information , else ..
- ** Syntax :
$netstat [option]
hint : option like [-r] [-s] ,make view of info page
example
netstat without options used to display all active localhost connections.
2- ifstat
- ** Function : a simple tool to report interface activity
- ** Syntax :
$ifstat
example
- ifstat need to install may be by default with system if not make this
◦ sudo apt-get install ifstat for debian
◦ yum install ifstat
3- tcpdump
- ** Function : tcpdump command is also called as packet analyzer . With tcpdump allow us to capture packets , then we can use it in analyziz ,we can save it in fie with extension .pcap
- ** syntax :
$tcpdump [option] [argument such as file name with extension type]
example
may be say that you don’t have perrmission fot that
- $ type su
- $ tcpdump -i eth0 #network interface
- making tcpdump files
◦ tcpdump -w test.pcap -i eth0
just after this make ls command and see that will make afile called test.pcap
4- dhclient :
- ** Function : Dynamic Host Configuration Protocol Client , what !!!
it provides a means for configuring one or more network interfaces using the Dynamic Host Configuration Protocol
- ** Syntax :
# dhclient [optiom] [argument]
example :
from abilities of dhclient that its can renews the ip address
- ** su
- ** dhclient eth0 #eth0 (my network interface)
5- nmap : (Short for network mapper)
- $ Function : nmap is a network exploration tool and security
- $ used as port scanner , so what is the mean of port scanner !
- $ Port scanner : A software program designed to go through a large listing of interesting ports or all available network ports and probe each port to see if it is available or open and accepting packets.
I am not good an asecurity guy so I am not good at this point , but let’s do some with this
- example :
notice PORT and STATE .
6- telnet :
Function : we can use telnet tool to connect to another remote computer .
- Syntax :
# telnet [ server name for example ]
this will ask u for >>
username :
password :
7- ssh : ( secure shell )
- # Function : is an encrypted protocol and associated program intended to replace telnet . It can also be used for creating secure tunnels .
- # Syntax :
# ssh [ server name for example]
8- minicom
- # Function : used to connect to serial device such as router and servers such as cisco router for example .
# Syntax :
minicom >>>> make connection with default serial device
minicom -s Edit minicom settings
9- ftp : ( file transfer protocol )
- ** Function : is commonly used for copying files to and from other computers. These computers may be at the same site or at different sites thousands of miles apart.
- ** Syntax :
$ftp [option] [host]
when type this this will open a shell begin with ftp> we can make ftp command
- this is the list of available command for ftp
10 – wget : File download utility for Linux systems
- ** Function : is a file download utility for the command line. It can be used to download files via HTTP and FTP protocols. In the above example, a file is downloaded from a
remote HTTP system and saved in the current directory.
- ** Syntax :
examples
▪ wget http://%5BHOST/FILE%5D
▪ wget ftp://[HOST/FILE]