Configuring Load Balancing in VMM Overview

 

Updated: May 13, 2016

Applies To: System Center 2012 SP1 - Virtual Machine Manager, System Center 2012 R2 Virtual Machine Manager, System Center 2012 - Virtual Machine Manager

Networking in Virtual Machine Manager (VMM) includes load balancing integration, so that you can automatically provision load balancers in your virtualized environment. Load balancing integration works together with other network enhancements in VMM. For information about these enhancements, see the list of topics at the end of this topic.

Load balancer integration

By adding a load balancer to VMM, you can load balance requests to the virtual machines that make up a service tier. You can add supported hardware load balancers through the VMM console or, for some configurations, you can use Microsoft Network Load Balancing (NLB). NLB is included as a possible load balancer when you install VMM. NLB uses round robin as the load-balancing method.

Note

  • In service tiers running Linux, NLB cannot be used.
  • With VM networks configured with network virtualization, NLB cannot be used.

For both of the previous configurations, hardware load balancing can be used instead.

To add supported hardware load balancers, you must install a configuration provider that is available from the load balancer manufacturer. The configuration provider is a plug-in to VMM that translates VMM PowerShell commands to API calls that are specific to a load balancer manufacturer and model.

Before you can use a hardware load balancer or NLB, you must create associated virtual IP (VIP) templates.

VIP templates

A virtual IP template contains load balancer-related configuration settings for a specific type of network traffic. For example, you could create a template that specifies the load balancing behavior for HTTPS traffic on a specific load balancer manufacturer and model. These templates represent the best practices from a load balancer configuration standpoint.

After you create a virtual IP template, users (including self-service users) can specify the virtual IP template to use when they create a service. When a user models a service, they can pick an available template that best matches their needs for the type of load balancer and the type of application.

Hardware load balancer workflow

The following list describes the hardware load balancer workflow to load balance a service tier:

  1. In the VMM console, during creation of a static IP address pool, the administrator configures a reserved range of virtual IP addresses.

    Note

    This step can be performed at any time before a service is deployed that uses a load balancer. Realize that you must have one virtual IP address for each service tier that uses load balancing.

  2. The administrator installs the load balancer configuration provider on the VMM management server.

    Note

    For information about supported load balancers and how to obtain configuration providers, see the “Prerequisites” section of How to Add Hardware Load Balancers in VMM.

  3. In the VMM console, the administrator adds the load balancer to VMM management. Through the Add Load Balancer wizard, the administrator does the following:

    • Selects the host groups where the load balancer will be available

    • Specifies the load balancer manufacturer and model

    • Specifies the load balancer DNS names (or IP addresses) and the port number that is used for load balancer management

    • Specifies the affinity to logical networks

    • Selects the configuration provider

    • Optionally tests the connection to the load balancer

  4. In the VMM console, the administrator creates one or more virtual IP templates. Through the Load Balancer VIP Template wizard, the administrator defines the following:

    • The port to use for the type of network traffic that will be load balanced

    • Whether the template applies to any supported load balancer or to a specific type of load balancer

    • The type of protocol to load balance (for example HTTPS)

    • Whether to enable session persistence

    • Optional health monitors that can be configured to periodically check that the load balancer is responsive

    • The type of load balancing method to use

    For more information, see How to Create VIP Templates for Hardware Load Balancers in VMM.

  5. A user (typically a self-service user) creates a service template. In the Service Template Designer window, they add a load balancer to a service tier, and then select which virtual IP (VIP) template to use. When the service is deployed, VMM automatically selects a virtual IP address from the reserved range in the static IP address pool and assigns it to the load balancer. This IP address is considered the “front-end” IP address for a load-balanced service tier. VMM also assigns static IP addresses to the virtual machines that make up the service tier. These are considered “back-end” dedicated IP addresses, as they are behind the load balancer.

  6. After the service is deployed, the administrator verifies in the VMM console which virtual IP address is being used as the front-end IP address for the service tier. The administrator then contacts the DNS administrator to create a DNS entry for the assigned virtual IP address. For example, if the front-end Web tier of a service is load balanced, the administrator can verify which virtual IP address is used for that tier. The DNS administrator can then create an entry in DNS for the name that users will specify to connect to the Web front-end. For example, the DNS administrator could create a DNS entry for ServiceName.contoso.com with the corresponding virtual IP address.

    Note

    For more detailed information about how to load-balance a service tier by using a hardware load balancer, see How to Add Networking Components to a Service Template and How to Configure a Hardware Load Balancer for a Service Tier.

NLB workflow

The following list describes the NLB workflow to load balance a service tier. However, in service tiers running Linux, or in a service where the VM networks are configured with network virtualization, you cannot use the NLB workflow. Instead, use the Hardware load balancer workflow, listed earlier in this topic.

This is the NLB workflow:

  1. In the VMM console, during creation of a static IP address pool, the administrator configures a reserved range of virtual IP addresses.

    Note

    This step can be performed at any time before a service is deployed that uses a load balancer. Realize that you must have one virtual IP address for each service tier that uses load balancing.

  2. In the VMM console, the administrator creates one or more virtual IP templates. Through the Load Balancer VIP Template wizard, the administrator defines the following:

    • The port to use for the type of network traffic that will be load balanced

    • The template type (in this case, the Specific template type, set to Microsoft NLB)

    • The type of protocol to load balance (TCP, UPD, or both)

    • Whether to enable session persistence

  3. A user (typically a self-service user) configures a service template by doing the following:

    • For the tier that will be load balanced, the user must specify a virtual machine template that meets the specific configuration requirements for NLB. For information about the configuration requirements, see How to Configure NLB for a Service Tier.

    • In the Service Template Designer window, the user adds a load balancer, and then selects which virtual IP (VIP) template to use.

    When the service is deployed, VMM automatically selects a virtual IP address from the reserved range in the static IP address pool and assigns it to a load-balanced service tier. VMM also assigns static IP addresses to the virtual machines that make up the service tier.

  4. After the service is deployed, the administrator verifies in the VMM console which virtual IP address is being used for a service. The administrator then contacts the DNS administrator to create a DNS entry for the assigned virtual IP address. For example, if the front-end Web tier of a service is load balanced, the administrator can verify which virtual IP address is used for that tier. The DNS administrator can then create an entry in DNS for the name that users will specify to connect to the Web front-end. For example, the DNS administrator could create a DNS entry for ServiceName.contoso.com with the corresponding virtual IP address.

    Note

    For more detailed information about how to load-balance a service tier by using NLB, see How to Configure NLB for a Service Tier.

Example scenario overview

The procedures in this section include examples that help demonstrate the concepts. For a summary of the examples that are used in this section, see the “Networking” section of the table in Preparing the Fabric Scenario in VMM.

Note

The examples are not meant to be prescriptive guidance for a lab setup. You should adapt the examples to your test environment.

In this section

To configure load balancing in your virtualized environment, follow these procedures:

Procedure Description
How to Add Hardware Load Balancers in VMM Describes how to add supported hardware load balancers to the VMM environment so that you can load balance service requests. Note: If you want to use Microsoft Network Load Balancing (NLB), you do not have to add a hardware load balancer. When you install VMM, NLB is automatically included as a load balancer. To use NLB, you must create NLB virtual IP templates, described in the last row of this table.
How to Create VIP Templates for Hardware Load Balancers in VMM Describes how to create virtual IP templates that you can use during service creation to help choose a hardware load balancer that best suits the need of the application.
How to Create VIP Templates for Network Load Balancing (NLB) in VMM Describes how to create NLB virtual IP templates that you can use during service creation to configure NLB for a service tier.

Next steps after configuring load balancing in System Center 2012 SP1 or System Center 2012 R2

For information about the next steps to take after configuring load balancing in System Center 2012 SP1 or System Center 2012 R2, see the following networking overviews:

Topic Step
Configuring Ports and Switches for VM Networks in VMM (for System Center 2012 SP1 and System Center 2012 R2) Configure port profiles and port classifications, and use them in logical switches, so that you can apply your port settings consistently to your network adapters and virtual network adapters. After configuring port settings, configure logical switches, and as needed, switch extensions (for Quality of Service (QoS), monitoring, or security).
Configuring VM Networks and Gateways in VMM (for System Center 2012 SP1 and System Center 2012 R2) Configure VM networks (on top of logical networks), which allow you to use network virtualization or other networking options. With VM networks that use network virtualization, you can also use gateways to increase connectivity.

Next steps after configuring networking

For information about the next steps to take after configuring networking, see the following topics:

Topic Step
Preparing the Fabric in VMM Configure additional fabric resources such as storage and library resources.
Adding and Managing Hyper-V Hosts and Scale-Out File Servers in VMM 
 Managing VMware ESX and Citrix XenServer in VMM
Configure hosts.
Creating and Deploying Virtual Machines and Services in VMM Deploy virtual machines, individually or as part of a service.

See Also

Configuring Logical Networking in VMM Overview
Common Scenarios for Networking in VMM in System Center 2012
Common Scenarios for Networking in System Center 2012 SP1 and System Center 2012 R2
Configuring Ports and Switches for VM Networks in VMM
Configuring VM Networks and Gateways in VMM
Configuring Networking in VMM