Microsoft Azure: Important changes to public IP addresses - Basic SKU will be retired

«Basic SKU» and «Standard SKU»

A public IP address is like a unique address on the internet. Just as the postal service needs your address to deliver letters, data on the internet needs this public number to find the right recipient. Every device that should be directly reachable from the internet - whether a web server, a cloud resource or your home internet router - needs such a public IP address.

«SKU» stands for «Stock Keeping Unit» and refers to a specific configuration or service tier of a product or service. In Azure, a SKU describes technical properties such as features or capacities. When it comes to IP addresses, this is specifically about the structure, functionality and security features of the public IP addresses in the Azure infrastructure.

A few years ago, Microsoft upgraded its concept in this regard and has since distinguished between the somewhat older feature set «Basic SKU» and the newer «Standard SKU». The change now taking place is happening because the cloud, and in particular its security requirements, is developing very dynamically due to rapid growth and many new features. Microsoft has therefore decided to retire the «Basic SKU» for Azure so that all Azure resources will soon be built on the more modern and more secure «Standard SKU».

What are the main advantages of the new «Standard SKU»?

As described at the outset, public IP addresses enable communication between your Azure resources and the internet. The switch from the Basic to the Standard SKU therefore offers several advantages:

• Security: Standard SKU IP addresses are more secure because they block inbound traffic unless it is explicitly allowed by a Network Security Group (NSG). In contrast, Basic SKU IP addresses are open to inbound traffic by default.

• Availability: Standard SKU IP addresses are designed so that they can be used across multiple Azure availability zones simultaneously (zone-redundant) or deployed in a specific zone (zonal). This means your applications remain reachable even if there are problems in a single zone. This significantly improves the stability and reliability of your services.

• Integration: With the Standard SKU you gain access to additional Azure services such as the Standard Load Balancer (for automatic load balancing), Azure Firewall and the NAT Gateway (both for further increasing security), which are not compatible with the Basic SKU.

• Advanced monitoring options: In future, detailed metrics on IP address usage and performance will be possible, as well as improved logging of connection attempts or diagnostics for connection problems.

What does this mean for my company and my infrastructure?

All companies that have been using the Basic SKU must switch to the Standard SKU by the deadline of 30 September 2025 to ensure that their resources continue to be supported.

The necessary steps for the switch are as follows - and we are of course happy to support our customers with these or take them over entirely:

1. Inventory: Identification of all Basic SKU IP addresses currently in use in the Azure environment.

2. Planning: It should be decided whether zone-redundant IP addresses are needed. If so, the new Standard SKU IP addresses must be created accordingly. If not, existing Basic SKU IP addresses can be upgraded to the Standard SKU.

3. Carry out the upgrade: For virtual machines, the public IP address is upgraded from Basic to Standard by disassociating it from the associated resources, then performing the upgrade and subsequently reassigning it. This may result in brief service interruptions, which can however be kept minimal.

4. Review network security groups: It must be ensured that appropriate NSGs are configured for all resources that previously used Standard SKU IP addresses, in order to allow the desired traffic.

This migration requires particular attention to, among other things:

• Security: Standard SKU IP addresses are more secure because they block inbound traffic unless it is explicitly allowed by a Network Security Group (NSG). In contrast, Basic SKU IP addresses are open to inbound traffic by default.

• DNS records: Changes to DNS records with public IP addresses may become necessary.

• Firewall rules: The security configurations should be reviewed and adjusted if necessary.

• Load balancers: A reconfiguration of the backend pools may be necessary.

• Application dependencies: After the switch, all connected services should be tested systematically to ensure that they remain reachable with the new configuration.

Conclusion

The switch from Basic SKU to Standard SKU IP addresses is an important step for your cloud infrastructure to continue ensuring the security, availability and integration of your Azure services. Through early and proactive planning and a step-by-step implementation of the changes, we jointly ensure that your infrastructure meets the upcoming requirements and continues to function optimally.

Our experts are happy to support you in planning and carrying out the migration. Contact us for individual advice.

Sources and further links

• Official announcement by Microsoft: Upgrade from Basic to Standard SKU public IP addresses in Azure by 30 September 2025 – Basic SKU will be retired
• Basic information on the Microsoft «Learn» platform about IP address versions as well as a comparison of Basic SKU vs. Standard SKU: German – English
• YouTube video at CloudPingPong; chapters relevant in this context on the topic of Basic SKU Public IP (from 17:02 min.) as well as on the related topic of Azure Outbound Connections (from 13:48 min.)