Getting Started with Oracle Cloud Infrastructure Load Balancing Classic

About Oracle Cloud Infrastructure Load Balancing Classic

With Oracle Cloud Infrastructure Load Balancing Classic, you can distribute incoming traffic across multiple Oracle Cloud Infrastructure Compute Classic instances running your applications in the Oracle Public Cloud. In this way, Oracle Cloud Infrastructure Load Balancing Classic provides similar features commonly available in a dedicated hardware load balancer or a separately managed instance of Oracle Traffic Director.

You create a load balancer from the Oracle Cloud Infrastructure Compute Classic console and then associate a pool of Compute instances with each load balancer. If a Compute instance is unavailable or unreachable, the load balancer automatically reroutes the traffic to the remaining compute instances in the server pool. When a Compute instance becomes available and is reachable again, the load balancer resumes routing traffic to that instance.

Additional Compute instances can be added or removed from the server pool as the request load changes, without disrupting the overall access to the application.

The overhead of encrypting and decrypting HTTPS traffic can be offloaded to the load balancer so that Compute instances can focus on their main work.

Note:

You need to first create a load balancer on an IP network before you can use PaaS Service Manager (PSM) to associate pools of PaaS instances or IaaS Compute instances with each load balancer.

Oracle Cloud Infrastructure Load Balancing Classic Terminology

Before you begin using Oracle Cloud Infrastructure Load Balancing Classic you should be familiar with basic load balancer terminology.

Term	Definition
Load balancer	An instance of Oracle Cloud Infrastructure Load Balancing Classic. Each load balancer has at least one listener, where it receives incoming requests, and at least one origin server pool, where it routes the requests, based on the load balancer properties and policies.
Client	The source of a request that is sent to the load balancer. Typically, this a request sent from a user’s browser to your application.
Origin server	A server or host computer to which the load balancer routes requests. In the context of the Oracle Cloud Infrastructure Load Balancing Classic, an origin server is an Oracle Compute Service instance.
Server pool	A pool of origin servers to which the load balancer routes requests. The load balancer selects a specific origin server in the pool using a load balancer algorithm.
Load balancing algorithm	The method a load balancer uses to determine which origin server in the server pool should receive a specific request. The current release of Oracle Cloud Infrastructure Load Balancing Classic supports the round-robin load balancer algorithm. In other words, the load balancer sends each new request to the next origin server in the server pool, using a set order. After it reaches the last server in the list, the load balancer returns to the first server in the list.
Server certificate	A digital certificate used to secure the connection between the clients and the load balancers. See About Load Balancer Digital Certificates.
Trusted certificate	A digital certificate used to secure the connection between the load balancer and the origin servers in a server pool. See About Load Balancer Digital Certificates.

About the Load Balancer IP Addresses and Canonical Host Name

When you use Oracle Cloud Infrastructure Load Balancing Classic to create a load balancer, two IP addresses and a canonical name are assigned to the load balancer. It is important to understand the purpose of these properties and why they are created before you implement a load balancing strategy.

When you create a new load balancer, Oracle Public Cloud creates two Compute instances to host the load balancer processes. These internal Compute instances (or virtual machines) are configured in a highly available configuration to ensure your load balancer is always available.

A canonical host name is also assigned to the load balancer. You use this canonical host name as the target URL for any requests to your applications, or you can map your custom, publicly available domain name to the canonical host name, so requests to your domain URL will be routed to the load balancer.

To map your public or custom domain URL to the load balancer, you (or your domain service provider) can create a canonical name (or CNAME) record that points to the load balancer canonical host name.

Interfaces to Oracle Cloud Infrastructure Load Balancing Classic

Oracle Cloud Infrastructure Load Balancing Classic provides the following ways to access, create, and manage your load balancers.

Type of Access	Description	More Information
Oracle Cloud Infrastructure Compute Classic Web-based console	This console provides a graphical user interface to create, manage, and modify your load balancer configurations.	How to Access Oracle Cloud Infrastructure Load Balancing Classic Using the Web Console
Oracle Cloud Infrastructure Load Balancing Classic REST API	Code REST requests to call methods to programmatically create, manage, and modify the load balancers you have created on Oracle Cloud.	REST API for Oracle Cloud Infrastructure Load Balancing Classic

Before You Begin with Oracle Cloud Infrastructure Load Balancing Classic

Before you begin using Oracle Cloud Infrastructure Load Balancing Classic, there are several steps you can take to prepare.

Understand the features of Oracle Cloud Infrastructure Compute Classic.
See About Compute Classic in Using Oracle Cloud Infrastructure Compute Classic
Understand the features of Oracle Cloud Infrastructure Load Balancing Classic.
See About Oracle Cloud Infrastructure Load Balancing Classic.

How to Begin with Oracle Cloud Infrastructure Load Balancing Classic

To begin using Oracle Cloud Infrastructure Load Balancing Classic, you must first get started with Oracle Cloud Infrastructure Compute Classic.

Request a trial or purchase a subscription for Oracle Cloud Service.
See Requesting and Managing Free Oracle Cloud Promotions or Buying an Oracle Cloud Subscription in Getting Started with Oracle Cloud.
Learn about the users and roles required for Oracle Cloud Infrastructure Compute Classic.
See About Compute Classic Roles in Using Oracle Cloud Infrastructure Compute Classic.
Learn about the users and roles required for Oracle Cloud Infrastructure Load Balancing Classic.

See About Oracle Cloud Infrastructure Load Balancing Classic Roles.
Create accounts for your users and assign them appropriate privileges and roles. See Adding Users and Assigning Roles in Getting Started with Oracle Cloud.

How to Access Oracle Cloud Infrastructure Load Balancing Classic Using the Web Console

You can access Oracle Cloud Infrastructure Load Balancing Classic from the Oracle Cloud Infrastructure Compute Classic console.

Sign in to your Cloud Account.
- For Oracle Cloud, see Signing in to Your Cloud Account in Getting Started with Oracle Cloud.
- For Oracle Cloud at Customer, click the Infrastructure Classic Console URL from the welcome email.
The Infrastructure Classic Console is displayed.
Under Services, click Compute Classic.
The Compute OPC console is displayed.
Click the Network tab in the Oracle Compute Cloud Service console.
Click the Load Balancers tab in the left pane, and then click Load Balancers.
The Load Balancers page displays any existing load balancers you have already created.
If you created a new load balancer recently and it is not appearing on the Load Balancers page, click to refresh the list of load balancers.

About Oracle Cloud Infrastructure Load Balancing Classic Roles

The following table summarizes the roles you can use to administer and use Oracle Cloud Infrastructure Load Balancing Classic.

Role	Description
Oracle Load Balancer Service Administrator	Users who are assigned this role can perform all the load balancer administration tasks, such as creating, modifying, and deleting load balancers—even those load balancers that are not owned by the user.
Oracle Load Balancer Service Operations	Users who are assigned this role can view, create, update, and delete load balancers that they own. For business continuity, consider creating at least two users with the Oracle Load Balancer Service Operations role. These users must be IT system administrators in your organization.
Oracle Load Balancer Service Read Only Privileges	Users who are assigned this role can view load balancers, but they cannot create, modify, or delete load balancers. The identity domain administrator can create users with this role in Oracle Cloud My Services.
Oracle Load Balancer Service Read Write Privileges	Users who are assigned this role can view and modify the attributes of an existing load balancer. However, they cannot create or delete load balancers.
Oracle Load Balancer Service Cert Management	Users who are assigned this role can create and delete load balancer certificates. They can also view and modify the attributes of an existing load balancer. However, they cannot create or delete load balancers.

See Adding Users and Assigning Roles in Getting Started with Oracle Cloud.

Using Load Balancer with Oracle PaaS Service Manager (PSM)

This guide describes how to create and manage load balancers from the Compute console for your Oracle Public Cloud Infrastructure as a Service (IaaS) environment.

Note that you can also create load balancers using Oracle PaaS Service Manager (PSM) which caters to the Oracle Cloud Platform as a Service (PaaS) environment. For example, when you are creating a Java Cloud Service instance you can also create a load balancer to use with the Java Cloud Service instance.

Notes have been added to this guide at appropriate places to indicate how the load balacers created using Oracle PaaS Service Manager (PSM) behave differently from the load balancers created from the Compute console.