Routes in Netplan... using routes: from the example says unknown key

Question

I have two NIC both connected to private networks one that goes to a dead end network and the other that can get to the internet through NAT.

When I bring up both the defaut route gets switched to the network that goes nowhere and none of the networking works anymore.

I've tried

routes:
 - to: 0.0.0.0/0
 via: <gateway address>
 metric: 1

from the freaking man page and netplan generate return unknown key routes

Got to love it when the documentation is evidently wrong.

Anyone know how I tell netplan which nic to use for the internet? Set a default route?

Very frustrating.

thanks.

EDIT: Okay... appears I've figured it out. Routes are associated with the interfaces rather than being global. As in...

ethernets:
  enp0:
    name: enp0s3
    addresses: [192.168.0.128/24]
    gateway4: 192.168.0.1
    nameservers:
      addresses: [8.8.8.8,8.8.4.4]
    routes:
     - to: <network>
     via: <gateway address>
     metric: 1
  enp1:
   <etc...>
    routes:
     - to: <network>
     via: <gateway address>
     metric: 5

At least generate doesn't throw errors and the routes apper to change.

score 6 · Answer 1 · answered Jan 05 '18 at 15:07

As you stated in your question, the netplan man page is wrong. In the example in the man page routes are incorrectly placed on the same level as ethernets:

network:
  version: 2
  renderer: NetworkManager
  ethernets:
    id0:
      match:
        macaddress: 00:11:22:33:44:55
      wakeonlan: true
      dhcp4: true
      addresses:
      - 192.168.14.2/24
      ...
  routes:
  - to: 0.0.0.0/0
    via: 11.0.0.1
    metric: 3

The correct way is to place the routes under the interface that the routes go via, for example:

network:
  ...
  ethernets:
    id0:
      addresses:
      - 10.0.0.2/24
      ...
      routes:
      - to: 192.168.0.0/16
        via: 10.0.0.1

score 1 · Answer 2 · answered Dec 25 '17 at 02:48

[SOLUTION} Sort of...

The netplan routing I put in the question is correct and works. My problem turns out to be with Virtualbox's networking being unstable. It will work fine a one point and then will fail for no apparent reason on the next re-boot.

Time to try VMPlayer.

score 0 · Answer 3 · answered Jun 03 '24 at 22:45

Apparently, I didn't provide my answer to this in the proper way... allow me to correct that.

Okay... appears I've figured it out. Routes are associated with the interfaces rather than being global. As in...

ethernets:
enp0:
    name: enp0s3
    addresses: [192.168.0.128/24]
    gateway4: 192.168.0.1
    nameservers:
      addresses: [8.8.8.8,8.8.4.4]
    routes:
     - to: <network>
     via: <gateway address>
     metric: 1
  enp1:
   <etc...>
    routes:
     - to: <network>
     via: <gateway address>
     metric: 5

At least generate doesn't throw errors and the routes appear to change.

-j

Routes in Netplan... using routes: from the example says unknown key

3 Answers3

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