If you ever had to use a hosting provider where you could purchase Additional IP’s or failover IP’s, you would have noticed that sometimes the IP’s used the same gateway as your original IP’s.
- OVH
- SoYouStart
The problem is when you use Cloudinit to deploy your VM’s on Ubuntu which uses netplan and unfortunately there isn’t a method to configure netplan through Cloudinit.
I’m using Proxmox and although you can create a custom network configuration for netplan.yml and deploy it as a snippet via cloudinit. This isn’t idea.
Canoical looks to have fixed the bug this year (2023) in January https://github.com/canonical/cloud-init/pull/1931a
However, that most likely relates to the new Ubuntu LTS. I’ve tested this within Ubuntu 20.04 and the appropriate config is in place. Here’s the generated /etc/netplan/50-cloud-init.yaml
[email protected]:~# cat /etc/netplan/50-cloud-init.yaml # This file is generated from information provided by the datasource. Changes # to it will not persist across an instance reboot. To disable cloud-init's # network configuration capabilities, write a file # /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following: # network: {config: disabled} network: version: 2 ethernets: eth0: addresses: - 147.135.0.0/24 match: macaddress: 02:00:00:79:e4:73 nameservers: addresses: - 213.186.33.99 search: - plantsbymail.com routes: - on-link: true to: default via: 15.0.0.254 set-name: eth0 eth1: dhcp4: true match: macaddress: 8a:ca:d3:4d:c9:28 set-name: eth1
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https://linuxconfig.org/how-to-add-static-route-with-netplan-on-ubuntu-22-04-jammy-jellyfish-linux