Netplan throws an error when attempting to load a config file, provides no details about what the error is

Question

Doing a clean install of Ubuntu Server 18.04 on a new machine. Currently attempting to configure my Ethernet network interface to use DHCP using netplan.

My config file, dynamic.yaml, reads as follows:

network:
    version: 2
    renderer: networkd
    ethernets:
        eno1:
            dhcp4: true

When I attempt to load this configuration with

sudo netplan try

I get an error which reads:

Error while loading /etc/netplan/dynamic.yaml, aborting.

sudo netplan --debug try

merely prints out "ERROR:Error while loading /etc/netplan/dynamic.yaml, aborting."

Any ideas what the error is? Or does anyone have any suggestions for how to get netplan to actually specify what the error is?

Solution

netplan is VERY fussy about .yaml file formatting. No tabs, specific indentation, and no extra spaces. Your .yaml looks ok syntactically, but try this variation...

network:
  version: 2
  renderer: networkd
  ethernets:
    eno1:
      dhcp4: true

sudo netplan generate # generate config files

sudo netplan apply # apply config

reboot # reboot the computer

Comments

[steeldriver]

The netplan-try manual page suggests there's a --debug switch: have you tried sudo netplan --debug try?

[user1819128]

Merely says the same thing unfortunately

[Boris Hamanov]

Does sudo netplan --debug generate give any more clues?

[user1819128]

Turns out I was using tabs instead of spaces - switching to spaces fixed the issue, Thanks!

[Todd Curry]

@heynnema, this answer made me get out my glasses and find the issue in my netplan -- tedious. Is there a YAML parsing utility (any language) that you know of to find issues programmatically?

[Boris Hamanov]

@ToddCurry Check out yamllint. It's in the Ubuntu repos.

[Todd Curry]

Brilliant, @heynnema -- thank you! When I googled, I also found yamllint.com, (which may/may not be secure, but) checks your yaml in a web form. You have set me on a path to yaml sanity!