We have an appservice hosting some odata api's in Azure. We are running an instance in Central US and another in East US 2. We have a Traffic Manager profile set up so a single url is balanced between the two instances. There is an intermittent issue, is there a way to hit a specific server as the endpoint to test them?
If you want to hit a specific server, you can directly access the instance with each instance domain name. Since Azure Traffic Manager works based on DNS, you can verify Traffic Manager settings using the tools like nslookup or dig to resolve DNS names. To effectively test a performance traffic routing method, you must have clients located in different parts of the world.
About the performance, please note that
The only performance impact that Traffic Manager can have on your website is the initial DNS lookup.
Traffic does NOT flow through Traffic Manager. Once the DNS lookup completes, the client has an IP address for an instance of your web site. The client connects directly to that address and does not pass through Traffic Manager. The Traffic Manager policy you choose has no influence on the DNS performance. However, a Performance routing-method can negatively impact the application experience. For example, if your policy redirects traffic from North America to an instance hosted in Asia, the network latency for those sessions may be a performance issue.
You may set the DNS TTL value low so that changes propagate quickly (for example, 30 seconds).
In addition, there are sample tools to measure DNS performance.
To troubleshoot a probe failure, you need a tool that shows the HTTP status code return from the probe URL. There are many tools available that show you the raw HTTP response.
Also, you can use the Network tab of the F12 Debugging Tools in Internet Explorer to view the HTTP responses.
Hope this information could help you.