Network Commands

1) ping
The ping command (named after the sound of an active sonar system) sends echo requests to the host specified on the command line, and lists the responses received.

READ  Computer Networks Lab Programs topics

Syntax: ping ipAddress or hostname
e.g
ping www.technerds.in ping – sends an ICMP ECHO_REQUEST packet to the specified host. If the host responds, an ICMP packet is received. One can “ping” an IP address to see if a machine is alive. It provides a very quick way to see if a machine is up and connected to the network.
2) netstat
It works with the LINUX Network Subsystem, it will tell us what the status of ports are ie. open, closed, waiting connections. It is used to display the TCP/IP network protocol statistics and information.
e.g netstat
netstat -a
3) tcpdump
This is a sniffer, a program that captures packets off a network interface and interprets them.
3) hostname
Tells the user the host name of the computer they are logged into.
e.g hostname
4) traceroute (In Windows use tracert )
traceroute will show the route of a packet. It attempts to list the series of hosts through which our packets travel on their way to a given destination.
Command syntax: traceroute machineName or ip
e.g traceroute wwwtechnerds.in
Each host will be displayed, along with the response times at each host.

5) finger
Retrieves information about the specified user.
e.g finger bce8001

6) ifconfig ( In Windows use ipconfig )
This command is used to configure network interfaces, or to display their current configuration.
e.g /sbin/ifconfig
/sbin/ifconfig -a

7) dig
The “domain information groper” tool. If a hostname is given as an argument, it outputs information about that host, including it’s IP address, hostname and various other information.
e.g dig technerds
8) telnet telnettelnet
telnet allows you to log in to a computer, just as if you were sitting at the terminal. Once your username and password are verified, you are given a shell prompt. From here, you can do anything requiring a text console.
e.g telnet bce0753
9) ftp
To connect to an FTP server.
Syntax: ftp ipaddress
e.g ftp 192.168.0.15

10) nslookup
nslookup returns the ipaddress of the given hostname and vice versa.
e.g nslookup www.technerds.in