Azure Traffic Manager subnet routing does not resolve

1
votes

I'm new to Azure. I'm trying to set up a Traffic Manager in order to DNS load balance between two endpoints. I have created a Traffic Manager with two endpoints with subnet routing. In order to test it, I looked up my public IP address and provided the CIDR range which contains my IP to one of the endpoint's subnet config. But somehow, my DNS lookup does not resolve to the intended target. I'm not sure if I'm doing something wrong or if my understanding of Azure Traffic Manager with subnet routing is incorrect.

I also have two follow up questions and would love to have answers to them as well.

  1. Are the endpoints configured ordered?
  2. Currently, it says that I can only configure 20 ranges by default. Is there a way to increase that limit?
1
azureazure-traffic-manager

1 Answers

3
votes

If I had to guess, I'd say the issue happens because it is not your IP address that Traffic Manager sees, but the DNS resolver's address. When you send out the DNS query, it most likely doesn't go directly to Traffic Manager. It goes to your default DNS server, which does a recursive query to Traffic Manager. So the request comes from there, not your machine.

Most likely you will need to look at different routing methods if this is the case.

This is mentioned in docs: https://docs.microsoft.com/en-us/azure/traffic-manager/traffic-manager-routing-methods#subnet-traffic-routing-method

After that, if Traffic Manager receives a DNS query for that profile, it will inspect the source IP address of that request (in most cases this will be the outgoing IP address of the DNS resolver used by the caller),