Cross V-Net AlwaysOn AG in Azure

Question

Hi Everyone
I have the following AlwaysOn setup in Azure
3 Servers:

Server 1 & Server 2 are in the same region within the same subnet/VNet
Server is in another region on its own subnet

When I created the cluster, it created it with a DNN automatically.
What happens with the load balancers now?
Can you have load balancers with a DNN cluster?

What would I need to do to get the AlwaysOn listener to work?

Answer 1

Hi @Derek Rhoda ,

You do not need Azure Load Balancer when you have DNN. You can configure a DNN listener for AG.

A distributed network name (DNN) listener replaces the traditional virtual network name (VNN) availability group listener when used with Always On availability groups on SQL Server VMs. This negates the need for an Azure Load Balancer to route traffic, simplifying deployment, maintenance, and improving failover.

Please refer to below MS document to get more information.

Tutorial: Prerequisites for availability groups in multiple subnets (SQL Server on Azure VMs)
Tutorial: Configure an availability group in multiple subnets (SQL Server on Azure VMs)
Configure a DNN listener for an availability group

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Answer 2

Hi @CathyJi-MSFT

I understand this but what happens in the case where the cluster spans VNets?