Network Security for Azure Storage

This document provides a comprehensive overview of the network security features available for Azure Storage accounts. Protecting your data in Azure Storage is paramount, and understanding these security mechanisms is key to building secure and robust applications.

Understanding Azure Storage Network Security

Azure Storage offers a variety of options to control network access to your storage accounts. These controls allow you to restrict access to specific IP addresses, virtual networks, or to make your data publicly accessible.

Firewall and Virtual Network Rules

The Azure Storage firewall and virtual network settings allow you to restrict network access to your storage account. By default, all network access to your storage account is allowed. You can change this default behavior to deny all access and then selectively allow access from specified IP addresses or virtual network subnets.

• Public Endpoints: When public endpoints are enabled, clients can connect to your storage account from any network.
• IP Firewall: You can specify a list of IP addresses or IP ranges from which clients are allowed to access your storage account.
• Virtual Network Service Endpoints: You can secure your storage account by binding it to a virtual network. Service endpoints enable you to secure your storage account by restricting access to a specific virtual network and by selecting specific subnets within that virtual network.
• Private Endpoints: Private endpoints provide a secure way to access your storage account over a private IP address within your virtual network, eliminating public internet exposure.

Configuring Network Security

Using the Azure Portal

You can configure network security settings through the Azure portal:

1. Navigate to your storage account in the Azure portal.
2. In the left-hand menu, under "Security + networking", select "Networking".
3. Choose the desired network access configuration: "Public endpoint (all networks)", "Public endpoint (selected networks)", or "Private endpoint connections".
4. If you select "Public endpoint (selected networks)", you can add IP addresses or virtual networks.
5. If you choose to use "Private endpoint connections", you can create or manage private endpoints.

Using Azure CLI

The Azure Command-Line Interface (CLI) can also be used to manage network security rules. Here are some example commands:

# Enable firewall for selected networks and add an IP range
az storage account update --name <storage-account-name> --resource-group <resource-group-name> --bypass none --default-action deny --add "networkAcls.ipRules" --ip-address "203.0.113.0/24"

# Disable public access entirely
az storage account update --name <storage-account-name> --resource-group <resource-group-name> --public-network-access disabled

# Create a private endpoint
az network private-endpoint create --name <private-endpoint-name> --resource-group <resource-group-name> --location <location> --subnet <subnet-id> --private-connection-resource-id "/subscriptions/<subscription-id>/resourceGroups/<resource-group-name>/providers/Microsoft.Storage/storageAccounts/<storage-account-name>" --group-ids "blob"
            

Network Security Best Practices

• Least Privilege: Grant only the necessary network access. Avoid allowing access from "all networks" unless absolutely required.
• Virtual Networks and Service Endpoints: Utilize virtual networks and service endpoints to keep traffic within the Azure network whenever possible.
• Private Endpoints: For maximum security, use private endpoints to ensure data travels over a private IP address.
• IP Filtering: If you need to allow access from specific on-premises or third-party IP addresses, use IP firewall rules.
• Regular Auditing: Periodically review your network security configurations to ensure they align with your security policies.

Key Security Features Summary