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Create a load balancer via the UI

Overview

In this walkthrough, you will use the Load Balancing interface in the Traffic app of the Cloudflare dashboard to create a load balancer in active-passive failover configuration. An active-passive failover configuration sends traffic to the servers in your active pool until a failure threshold (configurable) is reached. At the point of failure, Cloudflare then redirects traffic to the passive pool.


Before you begin

Be sure that you have the following:

Access to Load Balancing via one of the following:

  • An Enterprise plan with Load Balancing enabled.
  • An existing Free, Pro, or Business plan with a Load Balancing subscription. (Enable Load Balancing in the Traffic app.)
  • Load balancer hostname: The hostname for which the Cloudflare Load Balancer will manage traffic. The default hostname is the root hostname.
  • Origin servers (2): You will need access to at least two origin servers (origin-server-1 and origin-server-2, for example).
  • Location: Initially, we will configure only a single geographic region.

Create a load balancer

To start, we’ll create a load balancer using the Create a Load Balancer wizard in the Cloudflare Traffic app:

  1. Log in to the Cloudflare web application and select the site for which you want to create a load balancer.

  2. Open the Traffic app. If you see the Enable Load Balancing action instead of Create a Load Balancer, you will need to add the Load Balancing service to your customer plan in order to proceed. creating a load balancer using the traffic app 1

  3. Click Create a Load Balancer and provide the hostname for your load balancer—the DNS name at which the load balancer will be available.

    • To enable Session Affinity, select the By Cloudflare cookie only radio button and set the toggle switch to the On position. test

  4. Click Next to continue.


Create and add origin pools

In this example, we are going to create two pools: The primary pool, and a secondary, backup pool that will serve traffic if the primary fails. (To set up an active-active failover configuration, where all servers receive traffic at once, we would create only a single pool.)

  1. Click Create an origin pool. creating a load balancer using the traffic app 3

  2. Enter a name and origin server address for the first pool (this must be unique). This example uses an IP address, but if the origin server has a hostname, you can enter that instead. If you have configured pools already, you can select and add those here as well. creating a load balancer using the traffic app 4

  3. Click Save to continue.

  4. Add a second pool, similar to our first, by clicking Add Pool. Name the pool and provide an origin server name and address. Click Save. creating a load balancer using the traffic app 5 By default, pools are ordered by date created. You can reorder them by clicking the arrows next to the numerals in the Order column. creating a load balancer using the traffic app 6 For now, leave the order as it is.

  5. Click Next to continue.


Create, attach, and configure health checks

Now you will create monitors to run health checks that track the status of your origin servers.

  1. Click Attach Health Check and then Create a Health Check. creating a load balancer using the traffic app 7

  2. Click Next to attach the new health check to your primary pool. creating a load balancer using the traffic app 8

  3. Configure the health check:

    • The Health Threshold defines the number of healthy origin servers required to consider the pool healthy. If the number of healthy origin servers drops below the threshold, the pool will be marked unhealthy. There is only one origin server in this pool, so leave this value at 1.
    • Use the Health Check Regions field to specify geographic regions from which Cloudflare should send health check requests.
    • Enter an email address to receive notifications in the Notifications E-mail field. You can use a mailing list address or a PagerDuty address to share the notifications with a group. creating a load balancer using the traffic app 9

Simulate Zone pushes a request from Cloudflare Health Monitors through the Cloudflare stack as if it were a real visitor request to help analyze behavior or validate a configuration. It allows you to emulate the specified zone while probing. Monitors support authenticated origin pulls by entering the appropriate zone in the Simulate Zone field of the UI.

  1. Click Save.

  2. Repeat Steps 1–4 to attach a health check to your secondary pool. The status of your health check will be unknown until the results of the first check are available.

    Cloudflare polls for health status every 60 seconds. A green indicator represents a healthy status; red indicates a failed health check. Move the mouse over the indicator to display a tooltip with the reason for the failure (see Troubleshooting).

  3. Click Next to configure Geo Routing.

Monitors are highly configurable. For more detail and a complete list of properties, see Monitors.


Configure Geo Routing

Use Geo Routing to configure traffic policies and failover priority by geographic region. This is extremely useful when you want site visitors to access the origin server closest to them, which improves page-loading performance.

creating a load balancer using the traffic app 10

For this exercise, don’t add new regions. For more on Geo Routing, see Traffic steering.

Click Next to continue to the final step, Reviewing the Load Balancing configuration.


Review you load balancing configuration

Before creating your load balancer, the creation wizard presents your a summary of your configuration so that you can review and make changes.

creating a load balancer using the traffic app 11

Once you approve the configuration, click Save and Deploy to commit the configuration and immediately start your load balancer. Clicking Save as Draft will commit your configuration without starting the load balancer.

Once you have saved your load balancer configuration, you will be returned to the Load Balancing dashboard.

creating a load balancer using the traffic app 12

You can monitor your load balancers on the Load Balancing dashboard. The dashboard also provides quick access to common actions, such as creating new load balancers, managing monitors (health checks), and managing pools.


Share you load balancer with other sites

You can share your load balancer with other sites in your account by creating a canonical name (CNAME) record in the Cloudflare DNS app. This is useful for sharing configurations with multiple other domains, and you don’t have to create new load balancers for each site.

creating a load balancer using the traffic app 13

You can also configure separate load balancers for each domain and reuse monitors and pools. This is especially useful for changing the failover order for different domains, such as when your example.co.uk server has a different failover priority from example.com or example.com.au.