ip-route-add

Add a default route via gateway

$ sudo ip route add default via [gateway_ip]

$ sudo ip route add default dev [eth0]

$ sudo ip route add [192.168.1.0/24] via [gateway_ip] dev [eth0]

$ sudo ip route add [10.0.0.0/8] dev [eth0] table [100]

ip route add destination [options]

ip route add adds new routes to the kernel routing tables. Routes determine how packets are forwarded to their destinations based on the destination address.
A route specifies either a gateway (next-hop router) to forward packets to, or an interface for directly connected networks. Multiple routing tables can be used for policy routing.

default

Default route (0.0.0.0/0 or ::/0)

Next-hop gateway address

Output device name

Routing table (number or name)

Route preference (lower = preferred)

Preferred source address

Routing protocol identifier

Requires root privileges. Routes are not persistent across reboots without additional configuration. Adding conflicting routes may fail or create unexpected behavior.

The ip route command is part of iproute2, which replaced the older route command from net-tools. iproute2 provides unified management of all Linux networking features.

ip(8), ip-route(8), ip-route-list(8), ip-rule(8)