In the current series of posts, we are trying to setup a public load balancer. We already have created availability set, virtual network, virtual machines and load balancer. Please refer below posts in case you want to go through them:

• Azure Load Balancer – Getting Started
• Azure Load Balancer – Create availability set
• Azure Load Balancer – Create public load balancer

We have created a public load balancer. The backend pool and health probe has also been configured. Next step is to configure rules for load balancer.

What is a load balancing rule ?

A load balancing rule decides how the traffic would be load balanced and distributed to load balanced resources in the backend pool. A load-balancing rule maps a given frontend IP configuration and port to multiple backend IP addresses and ports.

For example, use a load-balancing rule for port 80 to route traffic from your frontend IP to port 80 of your backend instances.

Configure the load balancing rule

Navigate to the load balancer demo-lb, then select the Load balancing rules under Settings. Then click on Add.

On the new panel, you are required to provide below inputs:

• Name, the name of rule
• IP Version, lets keep it to the default value, IPv4
• Frontend IP address, the name that was given to the public IP address of load balancer
• Protocol, select TCP
• Port, the port on frontend for which this rule is applicable. Let it be 80.
• Backend port, the port number where traffic should be forwarded in the backend resource. Let this be 80 too.
• Backend pool, provide the name of backend pool that we already have created for the VMs.
• Health probe, provide the name of health probe we already have created.
• Session persistence, if you want to persist the sessions, then this setting is useful. For this demo, let it be set to None.
• Idle timeout (minutes), the time after which the session would be over. Let it be the default value.
• Floating IP, set it to default value i.e. Disabled.

After setting those inputs, click on OK to create the rule.

So, the load balancer rule is created. Next step is to verify the setup. Let’s do it in the next post of the series.

I hope you found this information useful. Let me know your thoughts.