Supported Operating Systems
Azure Virtual Machines (VMs) support a wide range of operating system (OS) images, including multiple versions of Windows Server and popular Linux distributions. The selected OS directly impacts your hourly compute cost, as Azure bundles applicable OS licensing fees into the VM price.
Azure Marketplace Images
In addition to base OS images, Azure offers preconfigured images through the Azure Marketplace. These images include the operating system plus commonly used software stacks tailored for specific workloads.
Example:
A WordPress deployment typically requires:
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Linux
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Apache
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MySQL
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PHP
Rather than installing each component manually, you can deploy a Marketplace image that includes the entire stack, saving time and reducing configuration complexity.
Custom Images
If a suitable image is not available, you can:
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Create your own disk image
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Upload it to Azure Storage
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Use it to provision an Azure VM
⚠️ Important: Azure supports 64-bit operating systems only.
Windows Server Software
All Microsoft software installed on Azure virtual machines must be properly licensed.
By default, Azure VMs include licenses for many common Microsoft products, such as:
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Windows Server (selected roles and features)
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Microsoft SQL Server
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Microsoft Exchange
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Microsoft SharePoint Server
Some VM offerings may include additional Microsoft software on a per-hour or evaluation basis. Any other third-party or custom software must be licensed separately.
✔️ Operating System Upgrade Limitation
Microsoft does not support in-place upgrades of the Windows OS on Azure VMs. To move to a newer Windows version:
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Create a new VM with the required OS version
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Migrate the workload to the new VM
Linux Server Software
Azure supports many Linux distributions, including:
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Ubuntu
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Red Hat Enterprise Linux (RHEL)
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CentOS by OpenLogic
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Debian
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Oracle Linux
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CoreOS
✔️ Linux OS Upgrades
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Fully open-source distributions generally support in-place OS upgrades
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Licensed distributions (such as RHEL or Oracle Linux) must follow vendor-specific upgrade rules, including BYOL (Bring Your Own License) requirements
Virtual Machine Connections
Azure provides multiple secure methods to connect to virtual machines.
Windows-Based Virtual Machines
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Accessed using Remote Desktop Protocol (RDP)
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Most Windows versions include native RDP support
Linux-Based Virtual Machines
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Accessed using Secure Shell (SSH)
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Common SSH clients include PuTTY, which supports SSH, SCP, Telnet, and serial connections
Detailed RDP and SSH connection steps are typically covered in follow-up lessons or documentation.
Azure Bastion Connections
Azure Bastion is a fully managed, platform-as-a-service (PaaS) offering that provides secure RDP and SSH connectivity directly from the Azure portal.
Key Benefits
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No public IP address required for VMs
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No exposure of RDP/SSH ports to the internet
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Encrypted connectivity over SSL
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No additional client software required
Azure Bastion enhances security by allowing administrators to connect to virtual machines safely without opening inbound ports or deploying jump servers.
