What is Changing? 

The infrastructure layer of Azure Event Hubs is being upgraded which will cause the IP addresses used by customer namespaces to change. These changes are being made as part of our continuous improvements to our platform. The IP addresses of our services can change and should not be considered static and unchanging. The changes being made will not alter billing or cause any service interruptions.  

Call to Action 

If you are using IP addresses in your egress firewalls to your Azure Event Hubs namespaces, you will need to configure your firewalls to use the fully qualified domain names for your specific namespaces, or the wildcard “*.servicebus.windows.net” domains. These will automatically resolve to the new IP addresses.