Configure a static IP on Ubuntu with a Netplan YAML file in /etc/netplan/, with dhcp4: no and an addresses: block, then run sudo netplan apply. The right way for a remote box is netplan try, which reverts after 120 seconds if the new config breaks connectivity.
Table of contents
The right YAML
The right Netplan YAML:
network:
version: 2
renderer: networkd
ethernets:
enp0s3:
dhcp4: no
addresses:
- 192.168.1.100/24
routes:
- to: default
via: 192.168.1.1
nameservers:
addresses:
- 1.1.1.1
- 8.8.8.8Applying the config
sudo netplan apply for a local box. sudo netplan try for a remote box.
Verifying
ip a show enp0s3, ip route, resolvectl status.
FAQ
What is the right interface name?
Run ip a to find the actual name. The right answer is to use the name that is state UP.
What if I lose connection after apply?
Wait 120 seconds if you used netplan try. If you used netplan apply, use the cloud console or IPMI to revert.
Can I have multiple IPs?
Yes, add them to the addresses: list.
What about cloud-init?
Disable with network: {config: disabled} in /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg.
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Useful related references: