• Legacy name: IP failover
• Linode offers a network helper which by default is on. Switching IPs works fine if you reboot after the switch with network helper on
• “Rumor has it” that you may not have to restart the nodes if you don't use network helper and configure the IPs yourself. I gave up on this approach after a few failed attempts.
• IP sharing adds secondary IP addresses to eth0 but never could figure out how to make use of that
• Since you can swap IPs between any 2 nodes, IP sharing seems meaningless, at least if using network helper and rebooting

• local machine will swap IP with remote machine
• local machine has linode-cli installed
• remote machine has private IP

ssh root@<REMOTEPRIVATEIP> "reboot"; linode-cli networking ip-assign --region us-central --assignments.address <REMOTEIP> --assignments.linode_id <LOCALID> --assignments.address <LOCALIP> --assignments.linode_id 3<REMOTEID>; sudo reboot

• Host a Website with High Availability on Linode
• Static IP on Linode
• Linode IP sharing with keepalived
• Linode introduction to high availability