Understanding Azure Networking for your VPS

Deploying a Virtual Private Server (VPS) on Azure involves leveraging a robust suite of networking services to ensure connectivity, security, and performance. This documentation provides an overview of key Azure networking components and how they relate to your VPS instances.

Core Networking Concepts

Virtual Networks (VNets)

A Virtual Network is the fundamental building block for your private network in Azure. It allows you to provision and manage a logically isolated section of the Azure cloud. Your VPS instances will reside within a VNet, enabling you to control IP addressing, routing, and security.

Subnets

Subnets are subdivisions of your VNet's IP address space. You can create multiple subnets within a VNet to segment your network and apply different security policies or access controls to different groups of resources.

Network Interfaces (NICs)

A Network Interface (NIC) connects your Virtual Machine (and thus your VPS) to its virtual network. Each VM can have one or more NICs, and each NIC is associated with a specific subnet within a VNet.

Key Networking Services

1. Virtual Network (VNet) Configuration

When you create a VPS (often as a Virtual Machine), you'll need to associate it with an Azure Virtual Network. You can create a new VNet or use an existing one. This involves defining an IP address space for your VNet, typically using private IP ranges (e.g., 10.0.0.0/16).

Example:


VirtualNetwork:
  Name: MyVNet
  AddressSpace: 10.0.0.0/16
  Location: East US

2. Subnetting for Isolation and Control

Within your VNet, create subnets for different purposes. For example, you might have a subnet for your web servers and another for your database servers. This enhances security by allowing you to apply granular network security group rules.

Example Subnet Definitions:


Subnets:
  - Name: WebServerSubnet
    AddressPrefix: 10.0.1.0/24
  - Name: DatabaseSubnet
    AddressPrefix: 10.0.2.0/24

3. Network Security Groups (NSGs)

NSGs are stateful packet inspection firewalls that enable you to filter network traffic to and from Azure resources in an Azure virtual network, a subnet, or a specific network interface. You'll use NSGs to define inbound and outbound security rules.

Common NSG Rules:

  • Allowing HTTP (port 80) and HTTPS (port 443) inbound traffic to your web servers.
  • Restricting SSH (port 22) access to specific IP addresses.
  • Denying all inbound traffic by default.

Example NSG Rule:


SecurityRule:
  Name: AllowHTTP
  Protocol: Tcp
  Direction: Inbound
  Priority: 100
  SourceAddressPrefix: '*'
  SourcePortRange: '*'
  DestinationAddressPrefix: '*'
  DestinationPortRange: '80'
  Access: Allow

4. Public IP Addresses and Load Balancing

To make your VPS accessible from the internet, you'll need to assign a Public IP address. For high availability and scalability, consider using Azure Load Balancer or Azure Application Gateway to distribute incoming traffic across multiple VPS instances.

5. Azure DNS for Name Resolution

Azure DNS provides a reliable and secure DNS hosting service for your Azure and non-Azure domain names. You can manage DNS records for your VPS to resolve domain names to their IP addresses.

6. VPN Gateway and ExpressRoute

For secure and private connections between your on-premises network and your Azure VNet, you can utilize Azure VPN Gateway or Azure ExpressRoute. This is crucial for hybrid cloud scenarios.

Best Practices for VPS Networking

  • Segment your network: Use subnets to isolate different types of workloads.
  • Implement least privilege: Configure NSGs with strict inbound and outbound rules.
  • Use private IP addresses internally: Reserve public IPs for external access only.
  • Monitor network traffic: Utilize Azure Network Watcher for insights.
  • Plan your IP addressing: Ensure sufficient IP space for future growth.

By understanding and effectively configuring these Azure networking components, you can build secure, scalable, and high-performing environments for your Virtual Private Servers.