OpenStack Octavia is a load balancing service that provides scalable and high availability load balancing for applications running on OpenStack clouds. Octavia uses a fleet of virtual machines called “amphorae” to distribute incoming traffic across multiple backend servers. In this response, I’ll provide you with a detailed overview of Octavia amphorae.
- What is an Amphora?
An amphora is a virtual machine instance that serves as a load balancer within the Octavia architecture. It acts as a network node that receives incoming traffic and distributes it to the appropriate backend servers. Amphorae are specifically designed for load balancing and are lightweight, stateless, and scalable. - Architecture:
Octavia utilizes a two-tier architecture that separates control plane operations from data plane operations. The control plane manages the overall orchestration and configuration of load balancing services, while the data plane, implemented by the amphorae, handles the actual traffic distribution. - Amphora Components:
Each amphora consists of several key components:- Amphora Image: Amphorae are instantiated from a predefined image that contains the necessary software components to function as a load balancer. This image typically includes an optimized operating system, required networking libraries, load balancing software, and other essential dependencies.
- Keepalived: Keepalived is a software package that runs on the amphorae to provide high availability for the load balancers. It uses the Virtual Router Redundancy Protocol (VRRP) to ensure failover capabilities in case of amphora or instance failures.
- HAProxy: HAProxy is a widely used open-source load balancing software that runs on the amphorae. It acts as the load balancer by receiving traffic from the virtual IP (VIP) address and forwarding it to the backend servers based on predefined load balancing algorithms and health checks.
- Networking Components: The amphorae have virtual network interfaces to receive and forward traffic. They are connected to the OpenStack Neutron networking service to ensure proper routing and connectivity between the amphorae and backend servers.
- Scalability:
Octavia provides horizontal scalability by allowing the deployment of multiple amphorae to handle increasing traffic loads. The load balancer functionality is distributed among multiple amphorae, enabling improved performance and fault tolerance. - Lifecycle Management:
Octavia manages the lifecycle of amphorae, including their creation, configuration, monitoring, and termination. When a load balancer is created, Octavia dynamically provisions the required number of amphorae based on the desired configuration and the current demand. Octavia also monitors the health of the amphorae and automatically replaces or scales them as necessary. - Integration with OpenStack:
Octavia integrates seamlessly with other OpenStack services, such as Neutron for networking and Keystone for authentication and authorization. It leverages the existing OpenStack infrastructure to provide load balancing as a service (LBaaS) to tenant applications.
Overall, Octavia amphorae are the workhorses of the Octavia load balancing service in OpenStack. They provide scalable, high-performance load balancing capabilities for applications running on OpenStack clouds, ensuring optimal traffic distribution and high availability.