Frequently asked questions for SQL Server on Azure VMs

Azure maintains virtual machine images for all supported major releases of SQL Server on all editions for both Windows and Linux. For more information, see the complete list of Windows VM images and Linux VM images.

Every two months, SQL Server images in the virtual machine gallery are updated with the latest Windows and Linux updates. For Windows images, this includes any updates that are marked important in Windows Update, including important SQL Server security updates and service packs. For Linux images, this includes the latest system updates. SQL Server cumulative updates are handled differently for Linux and Windows. For Linux, SQL Server cumulative updates are also included in the refresh. But at this time, Windows VMs aren't updated with SQL Server or Windows Server cumulative updates.

Yes. Only one image per major version and edition is maintained in Azure. For example, when a new SQL Server service pack is released, a new image is added to the gallery for that service pack and the SQL Server image for the previous service pack is immediately removed from the Azure portal. However, it's still available for provisioning from PowerShell for the next three months. After three months, the previous service pack image is no longer available. This removal policy also applies if a SQL Server version becomes unsupported when it reaches the end of its lifecycle.

Yes, by using PowerShell. For more information about deploying SQL Server VMs using PowerShell, see How to provision SQL Server virtual machines with Azure PowerShell.

Yes, but you must then register each SQL Server VM with the SQL IaaS Agent extension to manage your SQL Server VM in the portal, as well as utilize features such as automated patching and automatic backups. When registering with the extension, you also need to specify the license type for each SQL Server VM.

You can deploy a Windows Server VM (without SQL Server installed on it) and use the SQL sysprep process to generalize SQL Server on Azure VM (Windows) with the SQL Server installation media. Customers who have Software Assurance can obtain their installation media from the Volume Licensing Center. Customers who don't have Software Assurance can use the setup media from an Azure Marketplace SQL Server VM image that has the desired edition.

Alternatively, use one of the SQL Server images from Azure Marketplace to generalize SQL Server on Azure VM. You must delete the following registry key in the source image before creating your own image. Failure to do so can result in the bloating of the SQL Server setup bootstrap folder and/or SQL IaaS Agent extension in failed state.

Registry Key path:
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Setup\SysPrepExternal\Specialize

Yes, but you must then register each SQL Server VM with the SQL IaaS Agent extension to manage your SQL Server VM in the portal, as well as utilize features such as automated patching and automatic backups.

No. For virtual machine gallery images that include SQL Server, you must select one of the provided images either through the Azure portal or via PowerShell. However, you have the ability to deploy a supported Windows VM and self-install a supported SQL Server version to it. You must then register your SQL Server VM with the SQL IaaS Agent extension to manage your SQL Server VM in the Azure portal, as well as utilize features such as automated patching and automatic backups.

If the version and edition of SQL Server you're looking for isn't available in the Images drop-down on Azure Marketplace, deploy a Windows-only Azure virtual machine, and then manually install the version and edition of SQL Server you want. Register your SQL Server VM with the SQL IaaS Agent extension if you want to manage your SQL Server VM from the Azure portal.

If the version of Windows you're looking for isn't available in the SQL Server images found in the Images drop-down of Azure Marketplace, deploy a Windows-only Azure virtual machine with the desired edition, and then manually install the version and edition of SQL Server you want. Register your SQL Server VM with the SQL IaaS Agent extension if you want to manage your SQL Server VM from the Azure portal.

Developer and Express editions of SQL Server are available on Azure Marketplace, which doesn't charge you for the SQL Server license. If the Express or Developer edition isn't available for the version of SQL Server you're looking for, deploy a Windows-only Azure virtual machine, and then manually install the version and edition of SQL Server you want. Register your SQL Server VM with the SQL IaaS Agent extension if you want to manage your SQL Server VM from the Azure portal.

The easiest method is to create a virtual machine that includes SQL Server. For a tutorial on signing up for Azure and creating a SQL Server VM from the portal, see Provision a SQL Server virtual machine in the Azure portal. You can select a virtual machine image that uses pay-per-second SQL Server licensing, or you can use an image that allows you to bring your own SQL Server license. You also have the option of manually installing SQL Server on a VM with either a freely licensed edition (Developer or Express) or by reusing an on-premises license. Be sure to register your SQL Server VM with the SQL IaaS Agent extension to manage your SQL Server VM in the portal, as well as utilize features such as automated patching and automatic backups. For more information, see Pricing guidance for SQL Server Azure VMs.

There are three ways to do this. If you're an Enterprise Agreement (EA) customer, you can provision one of the virtual machine images. If you have Software Assurance, you can enable the Azure Hybrid Benefit on an existing pay-as-you-go (PAYG) image. Or you can copy the SQL Server installation media to a Windows Server VM, and then install SQL Server on the VM. Be sure to register your SQL Server VM with the extension for features such as portal management, automated backup and automated patching.

No. Customers need CALs when they use bring-your-own-license and move their SQL Server SA server / CAL VM to Azure VMs.

Yes. You can easily switch a pay-as-you-go (PAYG) gallery image to bring-your-own-license (BYOL) by enabling the Azure Hybrid Benefit. For more information, see How to change the licensing model for a SQL Server VM. Currently, this facility is only available for public and Azure Government cloud customers.

No. Changing the licensing model doesn't require any downtime for SQL Server as the change is effective immediately and doesn't require a restart of the VM.

No. Changing licensing models isn't supported on a classic VM. You can migrate your VM to the Azure Resource Manager model and register with the SQL IaaS Agent extension. Once the VM is registered with the SQL IaaS Agent extension, licensing model changes are available on the VM.

No. Through the SQL IaaS Agent extension, you can manage a single default instance, a single named instance, or, if the SQL Server VM has multiple instances, then one of those instances must be the default instance for it to be managed by the Azure portal. For more information on these limitations, see SQL Server IaaS agent extension.

Yes, Azure Cloud Solution Provider (CSP) customers can use the Azure Hybrid Benefit by first deploying a pay-as-you-go VM and then converting it to bring-your-own-license, if they have active Software Assurance.

To have a free passive license for a standby secondary availability group or failover clustered instance, you must meet all of the following criteria as outlined by the Product Licensing Terms:

1. You have license mobility through Software Assurance.
2. The passive SQL Server instance doesn't serve SQL Server data to clients or run active SQL Server workloads. It's only used to synchronize with the primary server and otherwise maintain the passive database in a warm standby state. If it's serving data, such as reports to clients running active SQL Server workloads, or performing any work other than what is specified in the product terms, it must be a paid licensed SQL Server instance. The following activity is permitted on the secondary instance: database consistency checks or CheckDB, full backups, transaction log backups, and monitoring resource usage data. You can also run the primary and corresponding disaster recovery instance simultaneously for brief periods of disaster recovery testing every 90 days.
3. The active SQL Server license is covered by Software Assurance and allows for one passive secondary SQL Server instance, with up to the same amount of compute as the licensed active server, only.
4. The secondary SQL Server VM utilizes the Disaster Recovery license in the Azure portal.

The passive SQL Server instance doesn't serve SQL Server data to clients or run active SQL Server workloads. It's only used to synchronize with the primary server and otherwise maintain the passive database in a warm standby state. If it's serving data, such as reports to clients running active SQL Server workloads, or performing any work other than what is specified in the product terms, it must be a paid licensed SQL Server instance. The following activity is permitted on the secondary instance: database consistency checks or CheckDB, full backups, transaction log backups, and monitoring resource usage data. You can also run the primary and corresponding disaster recovery instance simultaneously for brief periods of disaster recovery testing every 90 days.

The SQL Server Licensing Guide provides scenarios in which the Disaster Recovery Benefit can be utilized. Refer to your Product Terms and talk to your licensing contacts or account manager for more information.

Yes. The SQL Server installation media is located in a folder on the C drive. Run Setup.exe from that location to add new SQL Server instances or to change other installed features of SQL Server on the machine. Some features, such as Automated Backup, Automated Patching, and Azure Key Vault Integration, only operate against the default instance, or a named instance that was configured properly (See Question 3). Customers using Software Assurance through the Azure Hybrid Benefit or the pay-as-you-go licensing model can install multiple instances of SQL Server on the virtual machine without incurring extra licensing costs. Additional SQL Server instances can strain system resources unless configured correctly.

SQL Server 2012 to SQL Server 2019 can support 50 instances on a stand-alone server. This is the same limit regardless of in Azure on-premises. See best practices to learn how to better prepare your environment.

When you provision SQL Server on Azure VM, the SQL Server setup program installs a Microsoft Visual C++ Redistributable, which is required for SQL Server components to run properly. Your security software might send alerts about end of life (EOL) or obsolete software components due to the version of the Microsoft Visual C++ Redistributable components that were installed by SQL Server, particularly for older versions of SQL Server (SQL Server 2016 and earlier). According to the support lifecycle policy, Microsoft Visual C++ Redistributable components are supported as long as the product that installed them is supported. As long as your installed version of SQL Server is still supported, you can safely ignore this warning. We recommend not removing VC++ as it can break some SQL Server functionality.

Yes, but there are some considerations. First, SQL Server-associated billing may continue to occur depending on the license model for the VM. Second, as stated in the previous answer, there are features that rely on the SQL Server IaaS Agent Extension. If you uninstall the default instance without also removing the IaaS Agent extension, the extension continues to look for the default instance and might generate event log errors from the following two sources: Microsoft SQL Server Credential Management and Microsoft SQL Server IaaS Agent. One of the errors might be similar to the following:

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server wasn't found or wasn't accessible.

If you do decide to uninstall the default instance, also uninstall the SQL Server IaaS Agent Extension as well.

Yes, if the named instance is the only instance on the SQL Server, and if the original default instance was uninstalled properly. If there's no default instance, and there are multiple named instances on a single SQL Server VM, the SQL Server IaaS agent extension fails to install.

Yes, but you need to take additional steps to avoid being charged for your SQL Server instance as described in Pricing guidance. If you want to completely remove the SQL Server instance, you can migrate to another Azure VM without SQL Server preinstalled on the VM and delete the current SQL Server VM. If you want to keep the VM but stop SQL Server billing, follow these steps:

1. Back up all of your data, including system databases, if necessary.
2. Uninstall SQL Server completely, including the SQL IaaS Agent extension (if present).
3. Install the free SQL Express edition.
4. Register with the SQL IaaS Agent extension.
5. Change the edition of SQL Server in the Azure portal to Express to stop billing.
6. (Optional) Disable the Express SQL Server service by disabling service startup.

No. Portal management is provided by the SQL IaaS Agent extension, which relies on the SQL Server IaaS Agent extension. As such, the same limitations apply to the portal as the extension. The portal can either only manage one default instance, or one named instance as long as it's configured correctly. For more information, see SQL Server IaaS Agent extension

No. Using Microsoft Entra Domain Services isn't currently supported with SQL Server on Azure VMs. Use an Active Directory domain account instead.

Customers can change their version/edition of SQL Server by using setup media that contains their desired version or edition of SQL Server. Once the edition has been changed, use the Azure portal to modify the edition property of the VM to accurately reflect billing for the VM. For more information, see change edition of a SQL Server VM. There's no billing difference for different versions of SQL Server, so once the version of SQL Server has been changed, no further action is needed.

For SQL Server VMs deployed through Azure Marketplace, the installation media is located at C:\SQLServerFull. You can run Setup.exe from that location to add new SQL Server instances or to change other installed features of SQL Server on the machine. You can also copy this setup media to other virtual machines to install, or upgrade, that same version, and edition of SQL Server. Customers who have Software Assurance can obtain their installation media from the Volume Licensing Center.

Virtual machines give you control over the host machine, including when and how you apply updates. For the operating system, you can manually apply windows updates, or you can enable a scheduling service called Automated Patching. Automated Patching installs any updates that are marked important, including SQL Server updates in that category. Other optional updates to SQL Server must be installed manually.

If the OS is Windows Server 2008 R2 or later, yes. You can use any setup media to upgrade the version and edition of SQL Server, and then you can register with the SQL IaaS Agent extension. Doing so gives you access to all the benefits of the SQL IaaS Agent extension such as portal manageability, automated backups, and automated patching. If the OS version is Windows Server 2008, the extension is only supported with limited functionality.

You can get free extended security updates by moving your SQL Server as-is to an Azure virtual machine. Updates are available through the Windows Update channel. For more information, see end of support options.

Yes. You can configure a failover cluster instance using Azure shared disks, premium file shares (PFS), or storage spaces direct (S2D) for the storage subsystem. Premium file shares provide IOPS and throughput capacities that meet the needs of many workloads. For IO-intensive workloads, consider using storage spaces direct based on managed premium or ultra-disks. Alternatively, you can use third-party clustering or storage solutions as described in High availability and disaster recovery for SQL Server on Azure Virtual Machines.

Conceptually, running SQL Server on an Azure virtual machine isn't that different from running SQL Server in a remote datacenter. In contrast, Azure SQL Database offers database-as-a-service. With SQL Database, you don't have access to the machines that host your databases. For a full comparison, see Choose a cloud SQL Server option: Azure SQL (PaaS) Database or SQL Server on Azure VMs (IaaS).

Download and install the SQL Data tools from Microsoft SQL Server Data Tools - Business Intelligence for Visual Studio 2013.

Yes. Local DTC is supported for SQL Server 2016 SP2 and greater. However, applications must be tested when utilizing Always On availability groups, as transactions in-flight during a failover fail and must be retried. Clustered DTC is available starting with Windows Server 2019.

No. In fact, Azure SQL virtual machine and the SQL IaaS Agent extension don't store any customer data. Review the SQL IaaS Agent extension privacy statements to learn more.

To perform a cross-cluster migration of an availability group on SQL Server on Azure VMs, use the standard Azure Load Balancer SKU.

Yes. Azure premium file shares are supported for both failover cluster instances and standalone instances of SQL Server using the SMB protocol.

No. Microsoft automatically registers VMs provisioned from the SQL Server images in Azure Marketplace. Registering with the extension is required only if the VM was not provisioned from the SQL Server images in Azure Marketplace and SQL Server was self-installed.

Yes. Customers should register their SQL Server VMs with the extension if they didn't use a SQL Server image from Azure Marketplace and instead self-installed SQL Server, or if they brought their custom VHD. VMs owned by all types of subscriptions (Direct, Enterprise Agreement, and Cloud Solution Provider) can register with the SQL IaaS Agent extension.

Check the prerequisites for details.

The client credentials used to register the virtual machine should exist in any of the following Azure roles - Virtual Machine contributor, Contributor, or Owner.

Not initially. When you first register with the SQL IaaS Agent extension, binaries are copied to the SQL Server VM providing you with limited functionality. Once you enable a feature that relies on it, the SQL IaaS Agent is installed to the VM. Check the table of benefits for information about limited functionality.

October 2022 introduced the least privilege permissions model for the extension, granting minimal permissions necessary for each feature used by the extension. SQL Server VMs deployed after October 2022 via Azure Marketplace have the least privilege permissions model enabled by default. The extension uses sysadmin rights for SQL Server VMs that were deployed prior to October 2022, or self-installed SQL Server VMs that haven't manually enabled the least privilege model in the Azure portal. Review SQL IaaS Agent extension permissions to learn more.

The SQL virtual machines resource is a free resource that allows you to manage your SQL Server VM from the Azure portal. The SQL virtual machines resource is created when you deploy a SQL Server VM image from Azure Marketplace, or manually register a SQL Server VM with the SQL IaaS Agent extension. Azure can also create this resource automatically for existing VMs if a SQL Server instance is detected. There's no cost associated with SQL virtual machines resource.

No, starting September 2021, restarting the SQL Server service is no longer required when registering with the SQL IaaS Agent extension.

No. The SQL Server license type isn't an optional property when you're registering with the SQL IaaS Agent extension. You have to set the SQL Server license type as pay-as-you-go or Azure Hybrid Benefit when registering with the SQL IaaS Agent extension. If you have any of the free versions of SQL Server installed, such as Developer or Evaluation edition, you must register with pay-as-you-go licensing. Azure Hybrid Benefit is only available for paid versions of SQL Server such as Enterprise and Standard editions.

The license type automatically defaults to that of the VM image. If you use a pay-as-you-go image for your VM, then your license type is PAYG, otherwise your license type is AHUB by default.

Yes. If you deployed SQL Server from your own media, and installed the SQL IaaS Agent extension you can register your SQL Server VM with the extension to get the manageability benefits provided by the SQL IaaS Agent extension.

Yes. Navigate to the SQL virtual machines resource for your SQL Server VM, and choose SQL IaaS Agent Extension Settings under Help to open the repair page and repair the extension.

No. Registering a single VM with the SQL IaaS Agent extension isn't available in the Azure portal. Registering with the SQL IaaS Agent extension is only supported with the Azure CLI or Azure PowerShell.

No. A VM must have at least one SQL Server (Database Engine) instance to successfully register with the SQL IaaS Agent extension. If there's no SQL Server instance on the VM, the new Microsoft.SqlVirtualMachine resource is in a failed state.

Yes, provided there's a default instance on the VM. The SQL IaaS Agent extension registers only one SQL Server (Database Engine) instance. The SQL IaaS Agent extension registers the default SQL Server instance in the case of multiple instances.

Yes. SQL Server failover cluster instances on an Azure VM can be registered with the SQL IaaS Agent extension with limited functionality.

Yes. There are no restrictions to registering a SQL Server instance on an Azure VM with the SQL IaaS Agent extension if you're participating in an Always On availability group configuration.

None. There's no fee associated with registering with the SQL IaaS Agent extension. Managing your SQL Server VM with the extension is free.

Once you enable a feature that requires installing the agent, there's minimal impact from the two services that are installed to the OS. These can be monitored via task manager and seen in the built-in Windows Services console.

The two service names are:

• SQLIaaSExtension (Display name - Microsoft SQL Server IaaS Agent)
• SqlIaaSExtensionQuery (Display name - Microsoft SQL Server IaaS Query Service)

Remove the extension by deleting the extension from the SQL Server VM

No. The SQL IaaS Agent extension just enables additional manageability for SQL Server on Azure VM with no additional charges.

Yes, as long as the SQL Server VM was deployed on the public cloud using the Resource Manager model, and not the classic model. All other customers are able to register with the new SQL IaaS Agent extension. However, only customers with the Software Assurance benefit can use their own license by activating the Azure Hybrid Benefit (AHB) on a SQL Server VM.

When the Microsoft.Compute/VirtualMachine resource is dropped or moved, then the associated Microsoft.SqlVirtualMachine resource is notified to asynchronously replicate the operation.

The Microsoft.Compute/VirtualMachine resource isn't impacted when the Microsoft.SqlVirtualMachine resource is dropped. However, the licensing changes default back to the original image source.

No. Extended Security Updates (ESU) are applied automatically to the VM whether or not your SQL Server VM has registered with the SQL IaaS Agent extension.

Management modes were removed from the SQL IaaS Agent extension architecture. Starting in March 2023, registering with the SQL IaaS Agent extension initially just copies the binaries to the SQL Server VM and offers limited functionality. Once you enable a feature that relies on it, the SQL IaaS Agent is installed to the SQL Server VM.

No. The SQL IaaS Agent extension isn't supported with the following images - SQL Server Reporting Services, SQL Server Power BI Report Server, SQL Server Analysis Services.

Resources

Windows VMs:

• Overview of SQL Server on Windows VMs
• Provision SQL Server on Windows VMs
• High Availability and Disaster Recovery for SQL Server on Azure Virtual Machines
• Performance best practices for SQL Server on Azure Virtual Machines
• Application Patterns and Development Strategies for SQL Server on Azure Virtual Machines

Linux VMs:

• Overview of SQL Server on a Linux VM
• Provision SQL Server on a Linux VM
• FAQ (Linux)
• SQL Server on Linux documentation