Netplan does not support onlink gateway

[Waleed Hamra]

There are cases where the gateway is not in the same subnet as the IP of the machine. The kernel will by default not allow adding such a route, unless some options are specified.
For example, I could add such route using:

sudo ip route add default via xxx.xxx.xxx.xxx dev ens3 onlink

The onlink keyword skips the sanity check, the route gets added, and life is good.

systemd-network does support this, with a keywork in its .network file called gatewayonlink, according to the systemd.network man page, but netplan provides no option for me to tell it I want this option.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Mathieu Trudel-Lapierre (cyphermox)]

I've already noticed that "shortcoming", and I'll implement this as part of more work on the routing aspects of network configuration.

Marking Triaged/Wishlist; this is effectively a new "feature" since it's a new field we can use from systemd-networkd.

[Mathieu Trudel-Lapierre (cyphermox)]

Landed in git.

[Mathieu Trudel-Lapierre (cyphermox)]

Fix Released in netplan 0.34.