Invalid YAML for netplan: mapping values

Question

So, I am trying to set a static IP address for my Ubuntu Server 18.04.1 LTS. I took the ethernet config from this site.

network:
  version: 2
  renderer: networkd
  ethernets:
    enp3s0:
      dhcp4: no
      dhcp6: no
      addresses: [192.168.0.1/24]
      gateway4: 192.168.0.1
        nameservers:
          addresses: [192.168.0.1,8.8.8.8]

I carefully made sure there a space between each colon, didn't use tabs and made sure there's no leading spaces at the end of each line. Yet, when I run netplan --debug generate, I get:

Invalid YAML at /etc/netplan/01-network-card.yaml line 9 column 19: mapping values are not allowed in this context

Then, I compared the config with some other sample configs (1, 2, 3) and didn't notice much difference.

I also tried putting the addresses as:

addresses: [ "192.168.0.1/24" ]

As seen in this config with no luck. Whatever I try, it seems that the gateway4 line is always the problem. What am I doing wrong here?

Answer 1

Add space using the spacebar, not tab in above-mentioned line.