Linux Commands - Telecommunications and Network Operations

Download a file from a webpage

To download a file from a specific URL.

wget www.paginaweb.com/archivo

Download a file with resumption

Allows pausing the download and resuming it later.

wget -c www.paginaweb.com/archivo

Download a complete webpage

Downloads the entire structure of a webpage.

wget -r www.paginaweb.com

Show Ethernet configuration

Displays the network interface configuration.

ifconfig eth0

Activate the eth0 interface

Activates the specified network interface.

ifup eth0

Disable the eth0 interface

Deactivates the specified network interface.

ifdown eth0

Configure an IP address

Assigns an IP address to the network interface.

ifconfig eth0 192.168.1.1 netmask 255.255.255.0

Configure eth0 in promiscuous mode

Allows the interface to capture all packets on the network.

ifconfig eth0 promisc

Activate the eth0 interface in DHCP mode

Requests an IP address automatically from a DHCP server.

dhclient eth0

Show the routing table

Displays the configured routes in the system.

route -n

Configure default entry

Sets the default gateway.

route add -net 0/0 gw IP_Gateway

Configure static route

Adds a static route for a specific network.

route add -net 192.168.0.0 netmask 255.255.0.0 gw 192.168.1.1

Delete static route

Removes a specific static route.

route del 0/0 gw IP_gateway

Activate IP forwarding

Enables IP packet forwarding.

echo “1” > /proc/sys/net/ipv4/ip_forward

Show hostname

Displays the current hostname.

hostname

Resolve a name to an IP address

Looks up the IP address corresponding to a domain name.

host www.paginaweb.com

Resolve name and IP address

Provides information for both the name and the IP address.

nslookup www.paginaweb.com

Show link status of all interfaces

Displays the link status of the network interfaces.

ip link show

Show link status of eth0

Displays specific information about the eth0 interface.

mii-tool eth0

Show network card statistics

Provides detailed statistics for the network interface.

ethtool eth0

Show active network connections

Lists all active connections along with their PID.

netstat -tup

Show listening services on the system

Lists the network services that are listening.

netstat -tupl

Show HTTP traffic

Monitors HTTP traffic in real time.

tcpdump tcp port 80

Show available wireless networks

Scans and displays nearby Wi-Fi networks.

iwlist scan

Show configuration of a wireless network card

Displays the current configuration of a wireless interface.

iwconfig wlan0

Search in the Whois database

Obtains registration information for a domain.

whois www.paginaweb.com

SSH login

Connects to a remote server using SSH.

ssh [email protected]

SSH login with X11 forwarding

Allows running graphical applications on the remote server.

ssh -X usuario@maquina

SSH login on a specific port

Connects to a server on a port different from the default.

ssh -p 15000 usuario@maquina

Copy files using SCP

Securely transfers files between systems.

scp /archivo [email protected]:/directorio

Create an SSH tunnel

Establishes an SSH tunnel to redirect ports.

ssh -f [email protected] -L 2000:servidor.dominio.es:25 -N

Port forwarding using tunneling

Configures port forwarding through SSH.

ssh -v -L4001:localhost:4001 [email protected]