Can I get a fixed/static ip-address in Nectar?
Some availability zones now offer 'fixed/static' ip addresses, and others are working hard to implement this feature. This feature is known as 'Floating IPs' in OpenStack, and is part of the Networking features. You can read about it in our article about Private Networks, which describes requesting Floating IP quota and attaching Floating IPs to, and detaching them from your instances.
Please note that the instance actions Rebuild and Reboot, Suspend etc, will retain your instance's assigned non-floating IP address. Only upon Terminate/Delete will your non-floating IP address be returned to the pool and there is no reliable way to get it back.
As an alternative way to provide a non-changing address for your service, even when your IP address might occasionally change, you should consider using a DNS service, and keep the DNS record updated with the current IP address of your instance.