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Quickstart: Create an internal load balancer to load balance VMs using the Azure portal

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Get started with Azure Load Balancer by using the Azure portal to create an internal load balancer for a backend pool with two virtual machines. Other resources include Azure Bastion, NAT Gateway, a virtual network, and the required subnets.

Diagram of resources deployed for internal load balancer.

Note

In this example you'll create a NAT gateway to provide outbound Internet access. The outbound rules tab in the configuration is bypassed and isn't needed with the NAT gateway. For more information on Azure NAT gateway, see What is Azure Virtual Network NAT? For more information about outbound connections in Azure, see Source Network Address Translation (SNAT) for outbound connections

Prerequisites

Sign in to Azure

Sign in to the Azure portal.

Create NAT gateway

All outbound internet traffic traverses the NAT gateway to the internet. Use the following example to create a NAT gateway for the hub and spoke network.

  1. Sign in to the Azure portal.

  2. In the search box at the top of the portal, enter NAT gateway. Select NAT gateways in the search results.

  3. Select + Create.

  4. In the Basics tab of Create network address translation (NAT) gateway enter or select the following information:

    Setting Value
    Project details
    Subscription Select your subscription.
    Resource group Select Create new.
    Enter CreateIntLBQS-rg in Name.
    Select OK.
    Instance details
    NAT gateway name Enter myNATgateway.
    Region Select East US.
    Availability zone Select None.
    Idle timeout (minutes) Enter 15.

  5. Select the Outbound IP tab or select the Next: Outbound IP button at the bottom of the page.

  6. Select Create a new public IP address under Public IP addresses.

  7. Enter myNATgatewayIP in Name in Add a public IP address.

  8. Select OK.

  9. Select the blue Review + create button at the bottom of the page, or select the Review + create tab.

  10. Select Create.

Create the virtual network

When you create an internal load balancer, a virtual network is configured as the network for the load balancer.

A private IP address in the virtual network is configured as the frontend for the load balancer. The frontend IP address can be Static or Dynamic.

An Azure Bastion host is created to securely manage the virtual machines and install IIS.

In this section, you create a virtual network, subnet, and Azure Bastion host.

  1. In the search box at the top of the portal, enter Virtual network. Select Virtual Networks in the search results.

  2. In Virtual networks, select + Create.

  3. In Create virtual network, enter or select this information in the Basics tab:

    Setting Value
    Project Details
    Subscription Select your Azure subscription
    Resource Group Select CreateIntLBQS-rg.
    Instance details
    Name Enter myVNet
    Region Select East US

  4. Select the IP Addresses tab or select the Next button at the bottom of the page.

  5. In the IP Addresses tab, enter this information:

    Setting Value
    IPv4 address space Enter 10.1.0.0/16

  6. Under Subnets, select the word default.

  7. In Edit subnet, enter this information:

    Setting Value
    Subnet name Enter myBackendSubnet
    Subnet address range Enter 10.1.0.0/24
    Security
    NAT Gateway Select myNATgateway.

  8. Select Add.

  9. Select the Security tab.

  10. Under BastionHost, select Enable. Enter this information:

    Setting Value
    Bastion name Enter myBastionHost
    AzureBastionSubnet address space Enter 10.1.1.0/26
    Public IP Address Select Create new.
    Enter myBastionIP in Name.
    Select OK.

    Important

    Hourly pricing starts from the moment Bastion is deployed, regardless of outbound data usage. For more information, see Pricing and SKUs. If you're deploying Bastion as part of a tutorial or test, we recommend that you delete this resource once you've finished using it.

  11. Select the Review + create tab or select the Review + create button.

  12. Select Create.

    Note

    The virtual network and subnet are created immediately. The Bastion host creation is submitted as a job and will complete within 10 minutes. You can proceed to the next steps while the Bastion host is created.

Create load balancer

In this section, you create a load balancer that load balances virtual machines.

During the creation of the load balancer, you configure:

  • Frontend IP address
  • Backend pool
  • Inbound load-balancing rules

  1. In the search box at the top of the portal, enter Load balancer. Select Load balancers in the search results.

  2. In the Load balancer page, select Create.

  3. In the Basics tab of the Create load balancer page, enter, or select the following information:

    Setting Value
    Project details
    Subscription Select your subscription.
    Resource group Select CreateIntLBQS-rg.
    Instance details
    Name Enter myLoadBalancer
    Region Select East US.
    SKU Leave the default Standard.
    Type Select Internal.
    Tier Leave the default of Regional.

    Screenshot of create standard load balancer basics tab.

  4. Select Next: Frontend IP configuration at the bottom of the page.

  5. In Frontend IP configuration, select + Add a frontend IP configuration, then enter or select the following information:

    Setting Value
    Name Enter myFrontend
    Private IP address version Select IPv4 or IPv6 depending on your requirements.
    Setting Value
    Name Enter myFrontend
    Virtual network Select myVNet
    Subnet Select myBackendSubnet
    Assignment Select Dynamic
    Availability zone Select Zone-redundant

  6. Select Add.

  7. Select Next: Backend pools at the bottom of the page.

  8. In the Backend pools tab, select + Add a backend pool.

  9. Enter myBackendPool for Name in Add backend pool.

  10. Select IP Address for Backend Pool Configuration.

  11. Select Save.

  12. Select the Next: Inbound rules button at the bottom of the page.

  13. In Load balancing rule in the Inbound rules tab, select + Add a load balancing rule.

  14. In Add load balancing rule, enter or select the following information:

    Setting Value
    Name Enter myHTTPRule
    IP Version Select IPv4 or IPv6 depending on your requirements.
    Frontend IP address Select myFrontend.
    Backend pool Select myBackendPool.
    Protocol Select TCP.
    Port Enter 80.
    Backend port Enter 80.
    Health probe Select Create new.
    In Name, enter myHealthProbe.
    Select TCP in Protocol.
    Leave the rest of the defaults, and select OK.
    Session persistence Select None.
    Idle timeout (minutes) Enter or select 15.
    Enable TCP reset Select checkbox .
    Enable Floating IP Leave the default of unselected.

  15. Select Save.

  16. Select the blue Review + create button at the bottom of the page.

  17. Select Create.

Create virtual machines

In this section, you create two VMs (myVM1 and myVM2) in two different zones (Zone 1 and Zone 2).

These VMs are added to the backend pool of the load balancer that was created earlier.

  1. In the search box at the top of the portal, enter Virtual machine. Select Virtual machines in the search results.

  2. In Virtual machines, select + Create > Azure virtual machine.

  3. In Create a virtual machine, enter or select the values in the Basics tab:

    Setting Value
    Project Details
    Subscription Select your Azure subscription
    Resource Group Select CreateIntLBQS-rg
    Instance details
    Virtual machine name Enter myVM1
    Region Select (US) East US
    Availability Options Select Availability zones
    Availability zone Select 1
    Security type Select Standard.
    Image Select Windows Server 2019 Datacenter - Gen2
    Azure Spot instance Leave the default of unchecked.
    Size Choose VM size or take default setting
    Administrator account
    Username Enter a username
    Password Enter a password
    Confirm password Reenter password
    Inbound port rules
    Public inbound ports Select None

  4. Select the Networking tab, or select Next: Disks, then Next: Networking.

  5. In the Networking tab, select or enter:

    Setting Value
    Network interface
    Virtual network myVNet
    Subnet myBackendSubnet
    Public IP Select None.
    NIC network security group Select Advanced
    Configure network security group Select Create new.
    In the Create network security group, enter myNSG in Name.
    Under Inbound rules, select +Add an inbound rule.
    In Service, select HTTP.
    Under Priority, enter 100.
    In Name, enter myNSGRule
    Select Add
    Select OK
    Load balancing
    Place this virtual machine behind an existing load-balancing solution? Select the box.
    Load balancing settings
    Load-balancing options Select Azure load balancing
    Select a load balancer Select myLoadBalancer
    Select a backend pool Select myBackendPool

  6. Select Review + create.

  7. Review the settings, and then select Create.

  8. Follow the steps 1 through 7 to create one more VM with the following values and all the other settings the same as myVM1:

    Setting VM 2
    Name myVM2
    Availability zone 2
    Network security group Select the existing myNSG

Note

Azure provides a default outbound access IP for VMs that either aren't assigned a public IP address or are in the back-end pool of an internal basic Azure load balancer. The default outbound access IP mechanism provides an outbound IP address that isn't configurable.

The default outbound access IP is disabled when one of the following events happens:

  • A public IP address is assigned to the VM.
  • The VM is placed in the back-end pool of a standard load balancer, with or without outbound rules.
  • An Azure Virtual Network NAT gateway resource is assigned to the subnet of the VM.

VMs that you create by using virtual machine scale sets in flexible orchestration mode don't have default outbound access.

For more information about outbound connections in Azure, see Default outbound access in Azure and Use Source Network Address Translation (SNAT) for outbound connections.

Create test virtual machine

In this section, you create a VM named myTestVM. This VM is used to test the load balancer configuration.

  1. In the search box at the top of the portal, enter Virtual machine. Select Virtual machines in the search results.

  2. In Virtual machines, select + Create > Azure virtual machine.

  3. In Create a virtual machine, type or select the values in the Basics tab:

    Setting Value
    Project Details
    Subscription Select your Azure subscription
    Resource Group Select CreateIntLBQS-rg
    Instance details
    Virtual machine name Enter myTestVM
    Region Select (US) East US
    Availability Options Select No infrastructure redundancy required
    Security type Select Standard.
    Image Select Windows Server 2022 Datacenter - x64 Gen2
    Azure Spot instance Leave the default of unselected.
    Size Choose VM size or take default setting
    Administrator account
    Username Enter a username
    Password Enter a password
    Confirm password Reenter password
    Inbound port rules
    Public inbound ports Select None.

  4. Select the Networking tab, or select Next: Disks, then Next: Networking.

  5. In the Networking tab, select or enter:

    Setting Value
    Network interface
    Virtual network myVNet
    Subnet myBackendSubnet
    Public IP Select None.
    NIC network security group Select Advanced
    Configure network security group Select MyNSG created in the previous step.

  6. Select Review + create.

  7. Review the settings, and then select Create.

Install IIS

  1. In the search box at the top of the portal, enter Virtual machine. Select Virtual machines in the search results.

  2. Select myVM1.

  3. In the Overview page, select Connect, then Bastion.

  4. Enter the username and password entered during VM creation.

  5. Select Connect.

  6. On the server desktop, navigate to Windows Administrative Tools > Windows PowerShell > Windows PowerShell.

  7. In the PowerShell Window, execute the following commands to:

    • Install the IIS server.
    • Remove the default iisstart.htm file.
    • Add a new iisstart.htm file that displays the name of the VM.
    
 # Install IIS server role
 Install-WindowsFeature -name Web-Server -IncludeManagementTools

 # Remove default htm file
 Remove-Item  C:\inetpub\wwwroot\iisstart.htm

 # Add a new htm file that displays server name
 Add-Content -Path "C:\inetpub\wwwroot\iisstart.htm" -Value $("Hello World from " + $env:computername)

  8. Close the Bastion session with myVM1.

  9. Repeat steps 1 through 8 to install IIS and the updated iisstart.htm file on myVM2.

Test the load balancer

In this section, you test the load balancer by connecting to the myTestVM and verifying the webpage.

  1. In the search box at the top of the portal, enter Load balancer. Select Load balancers in the search results.

  2. Select myLoadBalancer.

  3. Make note or copy the address next to Private IP address in the Overview of myLoadBalancer. If you can't see the Private IP address field, select See more in the information window.

  4. In the search box at the top of the portal, enter Virtual machine. Select Virtual machines in the search results.

  5. Select myTestVM.

  6. In the Overview page, select Connect, then Bastion.

  7. Enter the username and password entered during VM creation.

  8. Open Microsoft Edge on myTestVM.

  9. Enter the IP address from the previous step into the address bar of the browser. The custom page displaying one of the backend server names is displayed on the browser. In this example, it's 10.1.0.4.

    Screenshot shows a browser window displaying the customized page, as expected.

  10. To see the load balancer distribute traffic across both VMs, navigate to the VM shown in the browser message, and stop the VM.

  11. Refresh the browser window. The page should still display the customized page. The load balancer is now only sending traffic to the remaining VM.

Clean up resources

When no longer needed, delete the resource group, load balancer, and all related resources. To do so, select the resource group CreateIntLBQS-rg that contains the resources and then select Delete.

Next steps

In this quickstart, you:

  • Created an internal Azure Load Balancer

  • Attached 2 VMs to the load balancer

  • Configured the load balancer traffic rule, health probe, and then tested the load balancer

To learn more about Azure Load Balancer, continue to:

What is Azure Load Balancer?