Traffic Manager President Edition FAQ: Understanding DNS-Based Traffic Management

As a key component of Azure's cloud infrastructure, Traffic Manager is designed to provide a scalable and reliable way to manage traffic for your applications. However, it's essential to understand the limitations and capabilities of this service, especially when it comes to tracking individual clients and implementing 'sticky' sessions.

One common misconception about Traffic Manager is that it can track individual clients and implement 'sticky' sessions, similar to other traffic management systems. Unfortunately, this is not possible due to the DNS-based nature of Traffic Manager. As explained in How Traffic Manager Works, the service operates at the Domain Name System (DNS) level, which means it doesn't have direct access to HTTP traffic between clients and servers.

This limitation is inherent to all DNS-based traffic management systems, including Traffic Manager. As a result, the service cannot provide tracking information for individual clients or implement 'sticky' sessions. Instead, it relies on DNS responses to direct clients to the appropriate service endpoints.

Another important aspect of Traffic Manager is that it doesn't see HTTP traffic between clients and servers. This means that clients connect directly to the service endpoint, rather than through Traffic Manager. The source IP address of the DNS query received by Traffic Manager belongs to the recursive DNS service, not the client.

So, what types of traffic can be routed using Traffic Manager? According to How Traffic Manager Works, the service can only route traffic that originates from the public internet to a set of endpoints that are also internet-facing. This means you cannot use Traffic Manager to route internal network traffic or traffic from private networks.

In terms of endpoint configuration, it's essential to understand that Traffic Manager doesn't provide an endpoint or IP address for clients to connect to. Instead, clients connect directly to the service endpoint, which must be configured at the service level, not within Traffic Manager.

To summarize, Traffic Manager is a DNS-based traffic management system designed to scale and distribute traffic across multiple endpoints. While it has limitations when it comes to tracking individual clients and implementing 'sticky' sessions, it excels in routing public internet traffic to internet-facing endpoints. By understanding how Traffic Manager works, you can make the most of this powerful tool in your Azure cloud infrastructure.

Traffic manager president edition faq