Latest

Learn about Azure UDR (User Defined Routes)

Learn about Azure UDR (User Defined Routes)

You can add unique routes to a VNET's routing table using Azure User Defined Routes (UDR), a feature of Azure Virtual Network (VNet). With the help of these routes, you can manage the traffic flow within your VNet and route it to particular next hops, such as virtual appliances or on-premises networks.

User-defined routes are chosen above the standard system routes when various route types are provided in a UDR route database. When more than one route leads to the same place, the most precise one is taken.

Fig 1.1- Azure UDR's

Azure's system routes define how IP traffic flows, allowing this flow of communication to take place. System routes control the flow of communication in the following scenarios:

  • From within the same subnet.
  • From a subnet to another within a VNet.
  • From VMs to the Internet.
  • From a VNet to another VNet through a VPN gateway.
  • From a VNet to your on-premises network through a VPN gateway.

Here are the general steps to create an Azure UDR:

Step 1: Log in to the Azure Portal

Step 2: You need to create a Resource first


Step 3: Click on the "Route table" option from the left side menu


Step 4: Click on the "+Add" button to create a new route table

In the new route table configuration page, fill in the required information, such as Name, Subscription and Resource Group


Step 5Now select the subnet column, then Click on Associate as shown below 


Step 6In the Associate subnet column, click Virtual network.

Step 7Select the virtual network in the Resource column.

Step 8In the Associate subnet column, click Subnet.

Step 9In the Choose subnet column, select the subnet

Step 10Click OK

By creating Azure UDRs, you can control the traffic flow in your VNet, directing traffic to specific next hops, such as virtual appliances or on-premises networks, which can be useful for scenarios such as traffic filtering and load balancing.

Other Articles you may interested in:
++++++++++++++++++++++++++++++++++++++++++++++++++++
Introduction to Azure Express Route - The Network DNA
Gateway Types in Azure - The Network DNA
Introduction to Azure Virtual Network (VNET) - The Network DNA
++++++++++++++++++++++++++++++++++++++++++++++++++++