My previous blog on System Center VMM 2012 SP1 HA & SQL Server 2012 AlwaysOn Availability Groups describes a complete walkthrough on enabling high availability on the host level, the database level and the VMM level. This is great for a Private Cloud but when you are a Service Provider additional functionalities are necessary.
Yesterday Microsoft announced Windows Azure Pack as the new name for Windows Azure for Windows Server. Windows Azure Pack combined with System Center Service Provider Foundation completes the end to end solution by Microsoft for Service Providers. I have done a couple of posts on the installation and configuration of both products. This blog will describe a complete step by step for enabling high availability in System Center Service Provider Foundation.
This blog resumes its configuration at the end of the previous blog on System Center VMM 2012 SP1 HA & SQL Server 2012 AlwaysOn Availability Groups.
System Center Service Provider Foundation is an extensible OData web service backed by an SQL database. The database will be added to the SQL AlwaysOn Availability Group. There are two ways to enable high availability for the extensible OData web service. A hardware load balancer or Network Load Balancing (NLB). I do not have a hardware load balancer in my lab environment, so I will describe the steps to enable NLB.
Network Load Balancing
There are some choices to make if you are going to use Network Load Balancing. NLB can be configured in two modes. Unicast or Multicast. In Unicast mode the cluster MAC address is assigned to the individual server NIC. The built-in MAC address of the server NIC is not used. In multicast mode the cluster MAC address is also assigned to the individual server NIC (used for client to cluster) but the built-in MAC address of the server NIC is also used (used for communication directed to the server). It is also possible to choose between a single NIC and multiple NICs per server. For more information on the advantages and limitations on each design choice have a look the documentation on TechNet here. http://technet.microsoft.com/en-us/library/cc759562(v=ws.10).aspx
In this blog I have chosen for NLB in Unicast Mode with a single NIC per server. In Windows Server 2008 Microsoft enabled the UnicastInterhostCommSupport by default. This allows the individual hosts to communicate with each other despite the server MAC address being overruled by the cluster MAC address.
Before configuring NLB in the virtual machines there is one essential settings that must be changed on the virtual machines.