Clarification on Batchpool Outbound access connectivity - Post September 30 2025

Hello,

Welcome to Microsoft Q&A,

Azure has announced that the classic compute node communication model will be retired on March 31, 2026. After this date, all Azure Batch pools must use the simplified compute node communication model. Classic mode pools are no longer supported post-retirement.

https://learn.microsoft.com/en-us/azure/batch/batch-pools-to-simplified-compute-node-communication-model-migration-guide

1. Until September 30, 2024, New pools default to classic if created within a virtual network.
2. After September 30, 2024, New pools default to simplified mode even inside vNets.
3. March 31, 2026, Classic mode fully retired — pools using it will stop functioning as expected.

Azure Batch pools that lack public IP addresses and rely on default outbound internet access will face disruptions after September 30, 2025.:

Default outbound internet access will be deprecated, meaning nodes must rely on user-configured NAT, Azure Firewall, or private endpoints.

• This specifically affects pools using simplified compute node communication without public IPs, where the default outbound was previously provided.

Post September 30, 2025, Outbound access to the internet via default channels will no longer work. While classic communication still allows outbound to Batch and storage, your pool may lose outbound internet connectivity for:

• Software updates
• External resource access

Please find the migration guide for reference, https://learn.microsoft.com/en-us/azure/batch/batch-pools-to-simplified-compute-node-communication-model-migration-guide

Please upvote and accept the answer if it helps!!