Introducing SQL Server Always On availability groups on Azure virtual machines
This article introduces SQL Server availability groups on Azure Virtual Machines.
Always On availability groups on Azure Virtual Machines are similar to Always On availability groups on premises. For more information, see Always On Availability Groups (SQL Server).
The diagram illustrates the parts of a complete SQL Server Availability Group in Azure Virtual Machines.
The key difference for an Availability Group in Azure Virtual Machines is that the Azure virtual machines, require a load balancer. The load balancer holds the IP addresses for the availability group listener. If you have more than one availability group each group requires a listener. One load balancer can support multiple listeners.
Additionally, on a Azure IaaS VM guest failover cluster, we recommend a single NIC per server (cluster node) and a single subnet. Azure networking has physical redundancy which makes additional NICs and subnets unnecessary on an Azure IaaS VM guest cluster. Although the cluster validation report will issue a warning that the nodes are only reachable on a single network, this warning can be safely ignored on Azure IaaS VM guest failover clusters.
When you are ready to build a SQL Server availability group on Azure Virtual Machines, refer to these tutorials.
Automatically create an availability group from a template
Manually create an availability group in Azure portal
You can also create the virtual machines yourself without the template. First, complete the prerequisites, then create the availability group. See the following topics: