Generally Available: Azure Virtual Network Manager UseExisting Mode for UDR management

Azure Virtual Network Manager UDR management now offers UseExisting mode, providing customers with greater flexibility and compliance control over user-defined routes (UDRs). With the UseExisting mode, Azure Virtual Network Manager detects and appends required routes to an existing route table associated with a subnet, preserving the original route table’s name, group, and tags. If no route table exists, Azure Virtual Network Manager automatically creates one as before. Customers seeking Azure Virtual Network Manager-managed route tables can continue using the existing Managed Only mode (the default). This general availability release empowers customers to: * Maintain governance compliance by retaining ownership of route table configurations * Simplify operations with seamless integration of AVNM automation into existing environments * Enhance flexibility by choosing how AVNM interacts with routing resources The UseExisting mode makes it easier than ever to adopt Azure Virtual Network Manager UDR management at scale—combining centralized automation with customer-driven governance and control. [Learn more](https://learn.microsoft.com/en-us/azure/virtual-network-manager/concept-user-defined-route).