O'Reilly logo
  • Angelie Soto thinks this is interesting:

The UDRs forward traffic to a virtual appliance such as a firewall. For that traffic to be allowed to pass to that virtual appliance, you must enable IP forwarding on the network interface of the VM.

From

Cover of Exam Ref 70-533 Implementing Microsoft Azure Infrastructure Solutions

Note

The traffic will be forward to another device like a firewall, for example.