Overview of Load Balancer

Describes how Load Balancer provides automated traffic distribution from one entry point to multiple servers reachable from your virtual cloud network.

The Load Balancer service provides automated traffic distribution from one entry point to multiple servers reachable from your virtual cloud network (VCN). The service offers a load balancer with your choice of a public or private IP address, and provisioned bandwidth.


Watch a video introduction to the Load Balancer service.

A load balancer improves resource utilization, facilitates scaling, and helps ensure high availability. You can configure multiple load balancing policies and application-specific health checks  to ensure that the load balancer directs traffic only to healthy instances. The load balancer can reduce your maintenance window by draining traffic from an unhealthy application server before you remove it from service for maintenance.

This overview contains the following separate topics:

You can also view topics on the following load balancer-related subjects:

Resource Identifiers

Learn about how Load Balancer resources use resource identifiers.

Most types of Oracle Cloud Infrastructure resources have a unique, Oracle-assigned identifier called an Oracle Cloud ID (OCID). For information about the OCID format and other ways to identify your resources, see Resource Identifiers.

Ways to Access Oracle Cloud Infrastructure

Learn the different ways you can access Oracle Cloud Infrastructure.

You can access Oracle Cloud Infrastructure using the Console (a browser-based interface) or the REST API. Instructions for the Console and API are included in topics throughout this guide. For a list of available SDKs, see Software Development Kits and Command Line Interface.

To access the Console, you must use a supported browser. To go to the Console sign-in page, open the navigation menu at the top of this page and click Infrastructure Console. You are prompted to enter your cloud tenant, your user name, and your password.

For general information about using the API, see REST APIs.

Monitoring Resources

Learn how to monitor the health, capacity, and performance of your Oracle Cloud Infrastructure resources by using metrics, alarms, and notifications.

You can monitor the health, capacity, and performance of your Oracle Cloud Infrastructure resources by using metrics, alarms, and notifications. For more information, see Monitoring and Notifications.

For information about monitoring the traffic passing through your load balancer, see Load Balancer Metrics.

Authentication and Authorization

Learn how the Load Balancer service uses authentication and authorization to manage access to its features and functionality.

Each service in Oracle Cloud Infrastructure integrates with IAM for authentication and authorization, for all interfaces (the Console, SDK or CLI, and REST API).

An administrator in your organization needs to set up groups , compartments , and policies  that control which users can access which services, which resources, and the type of access. For example, the policies control who can create new users, create and manage the cloud network, launch instances, create buckets, download objects, etc. For more information, see Getting Started with Policies. For specific details about writing policies for each of the different services, see Policy Reference.

If you’re a regular user (not an administrator) who needs to use the Oracle Cloud Infrastructure resources that your company owns, contact your administrator to set up a user ID for you. The administrator can confirm which compartment or compartments you should be using.

Limits on Load Balancing Resources

Learn about the limits on Load Balancer resources.

See Service Limits for a list of applicable limits and instructions for requesting a service limit increase.

Other limits include:

  • You cannot convert an AD-specific load balancer to a regional load balancer or the reverse.

  • The Load Balancer service supports IPv6 addresses for load balancers in the US Government Cloud only. IPv6 support is only for the load balancer itself, and not the backend.

  • The maximum number of concurrent connections is limited when you use stateful security rules for your load balancer subnets. In contrast, no theoretical limit on concurrent connections exists if you use stateless security rules. The practical limitations depend on various factors. The larger your load balancer shape, the greater the connection capacity. Other considerations include system memory, TCP timeout periods, TCP connection state, and so forth.


    To accommodate high-volume traffic, Oracle strongly recommends that you use stateless security rules for your load balancer subnets.

  • Each load balancer has the following configuration limits:

    • One IP address

    • 16 backend sets

    • 512 backend servers per backend set

    • 512 backend servers total

    • 16 listeners

Required IAM Policies

Learn about Identify and Access Management policies and how they apply to theLoad Balancer service.

To use Oracle Cloud Infrastructure, you must be granted security access in a policy  by an administrator. This access is required whether you're using the Console or the REST API with an SDK, CLI, or other tool. If you get a message that you don’t have permission or are unauthorized, verify with your administrator what type of access you have and which compartment  to work in.

For administrators: For a typical policy that gives access to load balancers and their components, see Let network admins manage load balancers.

Also, be aware that a policy statement with inspect load-balancers gives the specified group the ability to see all information about the load balancers. For more information, see Details for Load Balancing.

If you're new to policies, see Getting Started with Policies and Common Policies.