Reserved IP Details
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.
Reserved IPs let you redirect network traffic between any of your Droplets within the same datacenter. Assigning a reserved IP to a Droplet doesn’t replace or change its original public IP address.
Reserved IPs are free when assigned to a Droplet.
Reserved IPs are available in all datacenters. They are region-specific resources and can only be assigned to Droplets within the same datacenter.
Limits and known issues for Reserved IPs.