A DigitalOcean Reserved IP address is a publicly-accessible static IP address that you can assign to a Droplet and then reassign to another Droplet later, as needed. You can implement a failover mechanism with reserved IPs to build a high availability infrastructure.
To create a reserved IP from the control panel, click Create in the top right, then click Reserved IP.
This takes you to the Reserved IPs page. When you have no reserved IPs, this page invites you to choose a Droplet and assign one.
To reserve and assign a reserved IP to one of your Droplets, locate the Droplet using the Search for a Droplet text box, then click Assign Reserved IP.
Once you have at least one address assigned, you can reserve additional reserved IP addresses in specific datacenters without assigning them to Droplets by following the click here link in the header text.