Azure Traffic Manager ¶

Azure Traffic Manager is a DNS resolver, which helps in distributing the traffic to different endpoints globally based on the routing method you configure.

In other solutions, the request hits the front end and gets routed to the backend based on the rules you configure. However, in the case of Azure Traffic Manager, the requests hit the Azure Traffic Manager, and Azure Traffic Manager returns the endpoint address to the client as a DNS response. As the client is now aware of the endpoint, the client directly reaches out to the endpoint.

Tldr

The traffic doesn’t transit through the Azure Traffic Manager; instead, it returns the endpoint address to the client.

Resolution process¶

The request from the client reaches the recursive DNS servers, and the request gets forwarded to the Azure Traffic Manager. For example, if you have a website www.amarjitdhillon.com, you will map the www record as a CNAME to the DNS name of the Azure Traffic Manager.
A recursive DNS server will forward the request to the Azure Traffic Manager, and based on the routing method you have configured, Traffic Manager determines the best endpoint.
Once the endpoint is determined, Traffic Manager will return the IP address of the backend server as a DNS response to the DNS resolver
DNS resolver to return endpoint to the client.
Since the client knows the IP address to the endpoint, it will directly communicate with the endpoint returned by the Traffic Manager.

Routing methods¶

Various routing methods in Traffic Manager are:

Priority¶

You can set the priority for each endpoint, and the requests will be served by the endpoint that has the highest priority. If the endpoint with high priority is not healthy, then the endpoint with the second-highest priority serves the requests.

Weighted¶

Select Weighted routing when you want to distribute traffic across a set of endpoints based on their weight. Set the weight the same to distribute evenly across all endpoints.

Performance¶

Requests are routed to endpoints with lowest network latency.

Geographic¶

Requests are routed to endpoints based on the location of the client. This is ideal for serving websites in local language for customers accessing from a country.

Multi-value¶

This is used when we can have only IPv4/IPv6 addresses as endpoints. When a query is received for this profile, all healthy endpoints are returned.

Subnet¶

This is used to map the end-user IP address ranges to a specific endpoint.