Azure Documentation - Virtual Machines (Linux)

Introduction to Linux VMs in Azure

Azure supports popular Linux distributions like Ubuntu Server, Red Hat Enterprise Linux (RHEL), CentOS, SUSE Linux Enterprise Server, and Oracle Linux. You can deploy VMs from the Azure Marketplace or bring your own custom images.

Key benefits include:

• Flexibility: Wide choice of distributions and configurations.
• Scalability: Easily scale your VM resources up or down as needed.
• Cost-Effectiveness: Optimize costs with various pricing options and tools.
• Security: Robust security features and compliance certifications.
• Global Reach: Deploy VMs in Azure regions worldwide.

Creating a Linux Virtual Machine

You can create Linux VMs using several methods:

• Azure Portal: A user-friendly web interface for creating and managing resources.
• Azure CLI: A powerful command-line interface for scripting and automation.
• Azure PowerShell: Another command-line option for Windows and cross-platform environments.
• Azure Resource Manager (ARM) Templates: Declarative JSON templates for consistent deployments.
• Terraform: A popular Infrastructure as Code tool.

Example using Azure CLI:

az vm create \
  --resource-group MyResourceGroup \
  --name MyLinuxVM \
  --image UbuntuLTS \
  --admin-username azureuser \
  --generate-ssh-keys
                

Managing VM Lifecycle

Learn how to start, stop, restart, deallocate, and delete your Linux VMs.

• Starting and Stopping: Essential for managing costs and resources.
• Deallocation: Releases compute resources and stops billing for them.
• Resizing: Change the VM size to meet performance requirements.
• Disk Management: Attach, detach, and manage OS and data disks.

Connecting to Linux VMs

Securely connect to your Linux VMs using SSH.

• SSH Key Authentication: Recommended for enhanced security.
• Password Authentication: Less secure but sometimes necessary.
• Azure Bastion: A fully managed PaaS service that provides secure RDP and SSH access to your VMs.

Security Best Practices

Implement robust security measures to protect your Linux VMs:

• Use SSH key pairs instead of passwords.
• Configure Network Security Groups (NSGs) to restrict traffic.
• Keep your OS and applications updated with security patches.
• Enable Azure Security Center for threat detection and vulnerability management.
• Use managed identities for accessing Azure services.

Performance Tuning

Optimize the performance of your Linux VMs:

• Choose the appropriate VM size and series for your workload.
• Optimize disk I/O performance with appropriate storage configurations.
• Monitor resource utilization (CPU, memory, disk, network).
• Tune kernel parameters for specific applications.

Monitoring and Diagnostics

Leverage Azure Monitor to gain insights into your VM's health and performance.

• Azure Monitor Metrics: Collect performance counters.
• Azure Monitor Logs: Analyze logs and system events.
• Boot Diagnostics: Troubleshoot boot issues.

Cost Management

Reduce your Azure spending:

• Right-size your VMs.
• Utilize Reserved Instances for predictable workloads.
• Deallocate VMs when not in use.
• Use Azure Cost Management + Billing tools.

Automation

Automate common tasks:

• Azure Automation: Runbooks for scripting.
• Custom Script Extension: Run scripts during VM deployment.
• Cloud-init: For initial configuration of cloud VMs.