Is there a way to know which backend is serving the traffic?

Question

We have 3 backend linux servers where nodejs application is installed. Azure application gateway is configured to route the requests to these 3 backend nodes. However, we would like to setup a custom header in Application Gateway to understand at any point in time which backend is currently serving the traffic? Is there a way to achieve this in Application Gateway?

Answer 1

Hi @Baliga, Ramprasad (Cognizant),

Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.

I understand you want to know the which backend is serving the traffic.

To view this, you need to enable the diagnostic settings and allow the access log to be stored in the log analytics workspace.

Refer this link how to enable diagnostic settings in the application gateway:
Diagnostic logs - Azure Application Gateway | Microsoft Learn

see in log

In that log we can see the Backend serving the traffic.

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