IP Address

The UpCloud network has public and private IP addresses.

Public IP addresses are used to connect to the server from the Internet.

Private Utility network addresses are available for all servers within a single account, and can communicate with each other globally as long as the servers have the utility network interfaces configured. This is added to servers by default.

A server has a minimum of zero and a maximum of five public IPv4 and IPv6 addresses. Every server can have one utility network IPv4 address only, and must have at least one IP address. The UpCloud API assigns the IP addresses automatically in networks configured to use DHCP. IP addresses cannot be reserved for later use, except for floating IPs that can be reserved and switched from server to another freely within their specific zone.

The operating system running on the server will see a separate network interface per IP address. On a typical server, there are three network interfaces. The first network interface is assigned to the public network and the second to the Utility network. If the server has an IPv6 address configured it will use the third network interface. DHCP service is provided on all public IPv4 network interfaces and all private DHCP-enabled networks for automatic configuration of the correct IP address. IPv6 network interfaces should use stateless address autoconfiguration (SLAAC) with IPv6 privacy extensions disabled. On IPv6-only server DNS parameters can be obtained with stateless DHCPv6.

Additionally, there are floating IPs: IPv4 addresses that can be attached to any IPv4 interface in their specific zone (eg. de-fra1 or fi-hel2). Floating IP addresses can be instantly switched from one server to another when doing maintenance or dealing with technical issues. More information on floating IPs and their configuration can be found from our tutorials.

Release policy

The release policy defines what happens to an IP address when its dependent resource is deleted, such as a server or service it's attached to. The following values are supported:

release: The address is also deleted. This applies to both normal and floating IP addresses.

keep: For normal (non-floating) IP addresses, they are converted to detached floating IPs when their dependent resource is deleted. For floating IP addresses, they remain as detached floating IPs that can be reattached elsewhere.

Floating IP addresses are created with keep as default policy, ensuring they remain available even after dependency deletion.

The release policy can be set when creating a new IP address or modified for an existing one through the API.

Note that release policy functionality is currently only supported for public IPv4 addresses.

Service delegation

Assign existing Floating IPv4 addresses to a service instead of a server. This enables the service to manage the IP address and use your dedicated floating IP address in the service's DNS records.

Delegated IP addresses can be tracked with the is_delegated attribute in the API response.

When an IP address is delegated to a service, it becomes subject to specific access restrictions. The IP address becomes managed by the service until you explicitly remove it. During the delegation:

• You cannot delete the IP address.
• You cannot modify its MAC address.
• You can only update the release policy and PTR record.

These restrictions ensure service stability and are automatically lifted once the IP address is removed from the service and as long as the release policy is set to keep so the IP address remains available in your account.

Currently only Load Balancer supports IP address delegation.