Useful if you need to manually set your IP address, netmask, and gateway. (Such as when there isn’t a DHCP server around, or the DHCP server is broken, or if you accidentally set some device’s IP to be outside your local LAN’s configured IP range.)

These examples will use wlan0 as the example device. I am changing the IP address from 10.1.1.196 to 192.168.1.100

.

Turn on the device

\# ip link set dev wlan0 up

Get device’s current IP address

\# ip addr show dev wlan0
2: wlan0: mtu 1500 qdisc mq state UP qlen 1000
    link/ether 84:3a:4b:0a:cc:cc brd ff:ff:ff:ff:ff:ff
    inet 10.1.1.196/24 brd 10.1.1.255 scope global wlan0
    inet6 fe80::863a:4bff:fe0a:cccc/64 scope link 
       valid\_lft forever preferred\_lft forever 

Optional: Remove the device’s old IP address

\# ip addr del 10.1.1.196/24 dev wlan0

Give the device a new IP address

\# ip addr add 192.168.1.1/24 brd + dev wlan0

The “+” is shorthand, and auto-sets the broadcast address based on the IP address and netmask. E.g., the “+” above means “192.168.1.255”

Give the device a default route

\# ip route add default via 192.168.1.1 dev wlan0

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