IP vs IFCONFIG

commands.md

##Show network devices and configuration ¶

ifconfig   # ifconfig way
ip addr show
ip link show

##Enable a network interface ¶

ifconfig eth0 up
ip link set eth0 up

A network interface is disabled in a similar way:

ifconfig eth0 down
ip link set eth0 down

##Set IP address ¶

ifconfig eth0 192.168.0.77
ip address add 192.168.0.77 dev eth0

This was the simple version of the command. Often, also the network mask or the broadcast address need to be specified. The following examples show the ifconfig and ip variants.

Needless to say that the netmask can also be given in CIDR notation, e.g. as 192.168.0.77/24.

ifconfig eth0 192.168.0.77 netmask 255.255.255.0 broadcast 192.168.0.255
ip addr add 192.168.0.77/24 broadcast 192.168.1.255 dev eth0

##Delete an IP address ¶ With ip it is also possible to delete an address:

ip addr del 192.168.0.77/24 dev eth0

##Add alias interface ¶

ifconfig eth0:1 10.0.0.1/8
ip addr add 10.0.0.1/8 dev eth0 label eth0:1

##ARP protocol ¶ Add an entry in your ARP table.

arp -i eth0 -s 192.168.0.1 00:11:22:33:44:55
ip neigh add 192.168.0.1 lladdr 00:11:22:33:44:55 nud permanent dev eth0

Switch ARP resolution off on one device

ifconfig -arp eth0
ip link set dev eth0 arp off