Hello Dav,
Welcome to the Microsoft Q&A and thank you for posting your questions here.
I understand that you would like to know or established fact about Q3 2025 default Internet outbound access retired - MS CDN still available for Azure Virtual Desktop such as Windows Update, Office Updates, general AVD Services etc.
Starting September 30, 2025, new virtual machines (VMs) in Azure will no longer have default outbound internet access. This means that for these VMs to access the internet, including services like the Microsoft Content Delivery Network (CDN), Windows Updates, and Azure Virtual Desktop Service, you'll need to use explicit outbound connectivity methods.
The options you can use are:
- Azure NAT Gateway is a highly recommended method as it provides scalable and reliable outbound connectivity for your VMs, and Azure Load Balancer Outbound Rules is a method that allows you to configure outbound rules for VMs that are part of a backend pool - https://techcommunity.microsoft.com/t5/marketplace-blog/how-to-handle-the-2025-change-to-azure-vm-internet-access/ba-p/4021442
- Directly Attached Azure Public IP Address will help in assigning a public IP address directly to the VM
- Without these explicit methods, the VMs will not be able to reach external services. If you have existing VMs that rely on default outbound access, they will continue to work, but it's advisable to transition them to one of the explicit methods for better control and reliability - https://azure.microsoft.com/en-us/updates/default-outbound-access-for-vms-in-azure-will-be-retired-transition-to-a-new-method-of-internet-access
I hope this is helpful! Do not hesitate to let me know if you have any other questions.
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