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Announcing the Public Preview of the New Hybrid Connection Manager (HCM)

jordanselig's avatar
jordanselig
Icon for Microsoft rankMicrosoft
Apr 10, 2025

We are excited to announce the public preview of the new version of the Hybrid Connection Manager (HCM), a powerful tool designed to enhance connectivity and streamline the management of Hybrid Connections. This release marks a significant milestone in our ongoing efforts to provide robust and user-friendly solutions for managing hybrid environments with App Service.

Update May 28, 2025: The new Hybrid Connection Manager is now Generally Available. The download links shared in this post will give you the latest Generally Available version. Learn more Key Fe...
Updated Aug 28, 2025
Version 6.0
azure app service
nagagunda's avatar
nagagunda
Copper Contributor
Jun 25, 2025

Hi jordanselig​, Thanks for the post

I recently read the announcement regarding the public preview of the new Hybrid Connection Manager (HCM) 

We’ve had a Hybrid Connection setup running reliably for over five years, and I’m interested in exploring the new version.

🔄 Upgrade Path

Is there any official documentation or guidance available for upgrading from the existing HCM to the new version? I’d like to understand the steps involved, compatibility considerations, and any potential impact on existing connections.

🔐 Service Bus Gateway Clarification

I also came across a note in the updated documentation mentioning that outbound access is now required not only to https://*.servicebus.windows.net, but also to the Service Bus gateways that service the Hybrid Connection 

  • Is the Service Bus Gateway a new architectural component?
  • Could you please share a data flow diagram or architecture diagram that shows where the Service Bus Gateway fits in the overall Hybrid Connection setup?
  • Our on-prem servers currently allow outbound access to *.servicebus.windows.net. Do we need to make additional firewall changes to accommodate the new gateway endpoints?

Any insights or documentation links would be greatly appreciated as we plan our testing and potential upgrade.

Thanks in advance!

  • jordanselig's avatar
    jordanselig
    Icon for Microsoft rankMicrosoft
    Jul 01, 2025

    Hi nagagunda​ 

    We're still in public preview so we haven't released official docs for the upgrade path. However, installing the latest version of the HCM will replace any existing versions and copy over all existing connections. We recommend testing this out in a dev/sandbox environment to be sure the new version meets your needs and doesn't break your existing workloads. The new version has parity with the old version, so we don't expect issues, but please reach out to hcmsupport@service.microsoft.com with any issues and we will look into them with priority.

    This is not a change, additional gateways were added once the backend was upgraded to VMSS. The docs were unfortunately not updated until recently to reflect this. Your existing firewall with *.servicebus.windows.net should continue to work and you don't need any additional changes since the "*" covers the additional endpoints as well.

    This link will have details on the service bus gateway architecture https://learn.microsoft.com/azure/azure-relay/relay-what-is-it#architecture-processing-of-incoming-relay-requests if you're interested in learning more, but for App Service, this isn't completely necessary as we've tried to abstract these internal components away from the end application of them.