A floating IP is a publicly routable IP that you assign to your instance. It's called "floating" as the IP address is not directly connected to the interface of the instance. Instead the OpenStack platform sets up NAT to connect the public address to the internal address that the instance uses.
This has the advantage that you don't have to configure the instance to use the public IP address. It also prevents an IP address becoming unusable in case the instance crashes.
- From your Cloud Dashboard, under the Compute section, go to Instances. Next to your Instance, pull down the dropdown box on the right and choose Associate Floating IP:
- Select an IP in the Floating IP dialog box. if you don’t have any IPs listed in the dropdown, click the plus (+) sign to allocate a new floating IP to your account. Allocate the IP to your pool by clicking the Allocate IP button, after that you can assign the IP to your instance.
- Click "Associate" to assign the IP to your instance.