Configuring a Static Route Using the Command Line

To configure static routes with the nmcli command, use the following syntax:

nmcli connection modify connection_name +ipv4.routes "ip[/prefix] options(s) attribute(s)"[next_hop] [metric] [attribute=value] [attribute=value] ..."

+ipv4.routes: The plus (+) sign indicates that you're creating an IPv4 route. Without the sign, the command changes an existing IPv4 setting.
connection-name: Connection name or label for which you're creating a static route.
ip[/prefix]: IP address of the static route that you're creating. The IP address can also be in CIDR notation.
options: Options include next hop addresses and optional route metrics. These options are separated by spaces. For more information, see the nm-settings-nmcli(5) manual pages.
attributes: Attributes are entered as attribute=value and are also separated by spaces. Some attributes are mtu, src, type, cwnd, and so on. For more information, see the nm-settings-nmcli(5) manual pages.

Suppose that you have the following configurations:

Name of the connection: myconnection
Default gateway address: 198.51.100.1
Network to which you want to create a static route: 192.0.2.0/24

To create the route, ensure first that the default gateway for the route is directly reachable on the interface. Then, do the following:

Create the static route.

sudo nmcli connection modify myconnection +ipv4.routes "192.0.2.0/24 198.51.100.1"

To create several static routes in a single command, separate the route gateway entries with commas, for example:

sudo nmcli connection modify myconnection +ipv4.routes "192.0.2.0/24 198.51.100.1, 203.0.113.0/24 198.51.100.1"

Verify the new routing configuration.

nmcli connection show myconnection

–-
ipv4.routes:   { ip = 192.0.2.0/24, nh = 198.51.100.1 }
–-

Restart the network connection.
This step causes the connection to temporarily drop.
```
sudo nmcli connection up myconnection
```

Verify that the new route is active.

ip route

...
192.0.2.0/24 via 198.51.100.1 dev example proto static metric 100