Load Balancer

During this step of the tutorial we are going to:

1. Create public load balancer with public IP address. Our users will use this public IP as proxy address in the browser settings.
2. Add our virtual machines we created on the previous step as members of the backend pool of this load balancer.

Create load balancer

Select your resource group, click add and search for Load Balancer in the search box as shown on the following screenshot. Click Create button to start configuring the load balancer.

Specify the loadbalancer-node as the name of the load balancer, select type Public and SKU Standard. Also create the public IP address that will be assigned to this load balancer. Name the public ip address as loadbalancer-ip. See the following screenshot for reference.

The load balancer for our pool of proxy servers is now created. It should be visible in the resource group listing.

Create backend pool

Select the load balancer we have just created, then Backend Pool, Add and configure the backend pool as specified on the following screenshot. Note how we use the backend-vnet as virtual network and add our virtual machines as members of this backend pool.

Create health probe

The load balance needs to know when a virtual machine becomes unavailable or comes back online. This is done using so called health probe a separate TCP connection to the known port on the virtual machine. If connection can be made successfully - the virtual machine is healthy. To create such probe select the load balancer, health probes and then click Add. Name it loadbalancer-probe and configure as shown on the following screenshot.

Create incoming rule

The load balancer uses rules to distribute traffic coming to the public IP address to the backend pool of virtual machines. We now need to create such rule. Select your load balancer, then Rules and click Add to create a new rule. The following table and screenshot illustrate the required configuration.

Setting Name	Value
Name	loadbalancer-incoming-rule-3128
Protocol	Select TCP
Port	Type 3128
Backend port	Type 3128

Note that we set the outbound source network address translation (SNAT) to (Recommended) Use outbound rules to provide backend pool members access to the internet value.

Create outbound rule

loadbalancer-outbound-rule loadbalancer-outbound-ip