Identifying Interfaces and Addresses

In modern Linux systems, the ip command has replaced the older ifconfig for networking configuration and status checking.

Viewing IP Addresses (ip a)

ip a (short for ip address show) displays the addresses assigned to all network interfaces.

bash $ ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 ... inet 127.0.0.1/8 scope host lo 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 ... inet 192.168.1.50/24 brd 192.168.1.255 scope global dynamic eth0

• lo: The loopback interface (localhost).
• eth0 (or enp0s3): The primary ethernet connection (interface).
• 192.168.1.50: The IP address of your machine.
• /24: The subnet mask.

Viewing Routing Table (ip route)

Shows how traffic leaves your system (which gateway to use).

bash $ ip route default via 192.168.1.1 dev eth0 proto dhcp 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.50

• default via 192.168.1.1: This indicates your router's IP address (the default gateway).