Basic Linux Network Commands:

Basic Linux Network Commands:
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This category contains the most basic network commands available on Linux platform.
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w
Shows who is currently logged in and where they are logged in from.
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who
This also shows who is on the server in an shell.
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netstat
Shows all current network connections.
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netstat -an
Shows all connections to the server, the source and destination ips and ports.
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netstat -rn
Shows routing table for all ips bound to the server.
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netstat -an |grep :80 |wc -l
Show how many active connections there are to apache (httpd runs on port 80)
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top
Shows live system processes in a formatted table, memory information, uptime and
other useful info.
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While in top, Shift + M to sort by memory usage or Shift + P to sort by CPU usage.
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top -u root
Show processes running by user root only.
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route -n
Shows routing table for all ips bound to the server.
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route add default gw my_computer
Add a default gateway to my_computer.
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nslookup indianwebportal.com
Query your default domain name server (DNS) for an Internet name (or IP number)
host_to_find.
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traceroute indianwebportal.com
Have a look how you messages travel to yahoo.com
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tracepath indianwebportal.com
Performs a very similar function to traceroute.
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ifconfig
Display info on the network interfaces.
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ifconfig -a
Display into on all network interfaces on server, active or inactive.
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ifconfig eth0 down
This will take eth0 (assuming the device exists) down, it won’t be able to receive or
send anything until you put the device back “up” again.
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ifconfig eth0 up
You guessed it. This would take eth0 up and available to receive or send packets.
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/sbin/ifconfig eth0 192.168.10.12 netmask 255.255.255.0 broadcast 192.168.10.255
Assign IP 192.168.10.12, netmask and broadcast address to interface eth0.
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ifup eth0
Will bring eth0 up if it is currently down.
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ifdown eth0
Will bring eth0 down if it is currently up.
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ifcfg
Use ifcfg to configure a particular interface. Simply type ifcfg to get help on using
this script.
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ifcfg eth0 del 192.168.0.1
This command takes eth0 down and removes the assigned IP 192.168.0.1
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ifcfg eth0 add 192.168.0.2
This command brings eth0 up and assigns the new IP 192.168.0.2
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ping
Sends test packets to a specified server to check if it is responding properly
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ping indianwebportal.com
Sends echo requests to yahoo.com
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mii-tool
Checks what your duplex settings are.
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arp
Command mostly used for checking existing Ethernet connectivity and IP address
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hostname
Tells the user the host name of the computer they are logged into.
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findsmb
Used to list info about machines that respond to SMB name queries. findsmb with no
argument would find all machines possible. You can also specify a particular subnet
to localize search.
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host indianwebportal.com
Performs a simple lookup of an internet address using DNS.
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dig indianwebportal.com
The “domain information groper” tool. This example looks up information about
yahoo.com such as IP.
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dig -x 66.94.234.13
Looks up the address and returns the associated domain name. dig takes a huge number
of options (at the point of being too many), refer to the manual page for more
information.
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whois
Used to look up the contact information from the “whois” databases. Also reports IP
address and name server of domain as well as creation and expiration dates.
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ftp
File transfer protocol. Transfers files to another host (insecure)
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rdesktop
Display remote desktop on Linux Machine. You can use to connect to Windows.