# Overview

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Exoscale Elastic IPs (EIPs) provide static IP addresses that can be
persistently attached to multiple Compute instances within the same zone,
allowing seamless transition and consistent IP configurations across different
instances.


## Elastic IP Types
* __Manual Elastic IPs__
* __Managed Elastic IPs__

### Basic Behavior of Elastic IPs (EIPs)
Creation and Availability
: Elastic IPs are created for your organization. They remain available until
  you decide to delete them.

Attachment and Zone Binding
: Elastic IPs can be attached to one or multiple instances at any time, but can
  only be attached to Compute instances within the same zone.

Traffic Characteristics
: All incoming traffic towards an Elastic IP is redirected to the attached
  instances. All outgoing traffic is sent by the internal IP address attached
  to the instance. It **will not** appear as coming from the Elastic IP. When
  multiple instances are attached to an Elastic IP, traffic is distributed
  among them with **no guarantee of even load distribution**.

### Customizable Behavior
Both manual and managed Elastic IPs have distinct characteristics, their
behavior can be customized further based on requirements. Distinct
Characteristics of Manual and Managed Elastic IPs are:



## Manual Elastic IPs
Configuration
: Manual Elastic IPs need to be manually enabled on the instance, this type
  offers more flexibility but requires more manual configuration.

Traffic Perception
: Internally, instances attached to a manual Elastic IP see traffic as coming
  directly to the Elastic IP address, this is different from managed Elastic
  IPs, where incoming traffic is seen as coming to the native IP address of the
  attached instance.

Outgoing Traffic
: Outgoing traffic can originate from the manual Elastic IP, allowing the
  instance to use it as a traffic source, albeit with some limitations.


## Managed Elastic IPs
Configuration
: Managed Elastic IPs do not require manual action on your part for the
  instance itself. Once attached, a managed Elastic IP transparently routes
  traffic to the instance.

Traffic Routing
: Includes basic health check capabilities, ensuring traffic is routed only to
  healthy instances.

Traffic Perception
: Instances see incoming traffic as if it's from the native IP address, making
  it impossible to differentiate traffic based on the target IP.

Outgoing Traffic
: Outgoing traffic will always appear from the native IP address, unlike manual
  Elastic IPs.


## Elastic IPv6 Prefix
Exoscale Compute instances can optionally be assigned a public IPv6 address either during creation or afterward. This IPv6 address is partially derived from the instance's unique MAC address, making it intrinsically tied to the instance. Therefore, when an instance is destroyed, its public IPv6 address is permanently released.

In scenarios where a persistent IPv6 address is desirable, such as employing multiple IPv6 addresses for a single use case, an Elastic IPv6 prefix can be used. The Elastic IPv6 prefix is a Compute resource that provides your organization with an entire IPv6 prefix (with prefix length /96), which can be attached to one or several instances in addition to their primary IPv6 address.

To utilize these prefixes, instances must have
[IPv6 enabled]({{< ref "/product/networking/ip/overview/#adding-ipv6-to-new-instance" >}}).
Your organization can attach multiple Elastic IPv6 prefixes as needed. Unlike its IPv4 counterpart, an Elastic IPv6 prefix contains over 4 billion addresses, providing ample resources to cater to your instances’ networking requirements.


## Terminology
Native IP Address
: The primary IP address automatically assigned to a Compute instance. It is
  distinct from any Elastic or additional IPv6 addresses that might be
  assigned.

Elastic IP
: A static public IP address that an organization can attach to one or multiple
  Compute instances in addition to their native IP addresses. Elastic IP
  addresses are created for the organization and remain available until they
  are explicitly deleted.

Manual Elastic IP
: A type of Elastic IP that requires manual configuration on Compute instances.
  It provides more flexibility, allowing traffic to originate from the manual
  Elastic IP address if configured correctly.

Managed Elastic IP
: A type of Elastic IP that does not require manual configuration. When
  attached, it automatically routes traffic to Compute instances.

Elastic IPv6 Prefix
: A Compute resource providing an entire IPv6 prefix (with a prefix length of
  /96) that can be assigned to one or several instances. It offers multiple
  IPv6 addresses for use within an organization.

Traffic Distribution
: The process by which incoming traffic is distributed among multiple instances
  attached to a single Elastic IP. There is no guarantee of even load
  distribution across instances.

Zone
: A specific geographical location where Exoscale infrastructure is available.
  Compute instances and Elastic IPs are bound to a certain zone, meaning
  resources must be within the same zone to be attached to each other.


## Features
All Exoscale instances are provisioned with a native IPv4 address, leased from
a global pool and intrinsically tied to the Compute instance. However, upon
instance termination, the IP address is released back to the pool with no
guarantee of reacquisition.

Elastic IPs
: Ensure continuity with Elastic IPs, designed for persistent address
  allocation across instances. Elastic IPs supplement native addresses and can
  attach to multiple instances simultaneously.

Persistent Usage
: Achieve IP persistence through Elastic IPs, mitigating address changes upon
  instance destruction. Seamlessly reroute traffic with an Elastic IP when
  transitioning between underlying instances.

Multi-IP Scenarios
: Elastic IPs address complex requirements like multi-TLS certificate usage or
  running numerous service instances on a single machine.

> [!NOTE]
> Leverage Elastic IPs for operational continuity and flexibility across your network architecture.








