AZ-700 Question 199
Single answerYou have an existing Azure Application Gateway configured with a single-site HTTPS listener on port 443 for a production application (prod.contoso.com). Your team wants to add a new dev environment (dev.contoso.com) on the same Application Gateway but route requests to a separate backend pool. You also plan to use the same public IP address. Which approach should you take to ensure that traffic for dev.contoso.com is routed to the dev backend without interfering with production traffic?
- A
Create a new multi-site listener on port 443, specifying dev.contoso.com as the host name and associating it with the dev backend pool.
- B
Add a second domain binding to the existing single-site listener to handle both prod.contoso.com and dev.contoso.com on the same listener.
- C
Configure a path-based routing rule '/dev' on the existing single-site listener to direct requests to the dev backend pool.
- D
Add a second front-end IP configuration to the Application Gateway, assign it to dev.contoso.com, and reuse the existing single-site listener.
Show answer and explanation
Correct answer: A
Explanation
In Azure Application Gateway, single-site listeners are scoped to a single fully qualified domain name (FQDN). When you need to route different host names (e.g., subdomains) to separate backend pools, each host name should have its own multi-site listener. This setup allows the Application Gateway to direct requests based on the host header. For more details, see the official Microsoft documentation on multi-site hosting with Application Gateway at https://learn.microsoft.com/azure/application-gateway/multiple-site-overview.
- A. Correct.
Correct. For hosting multiple subdomains on a single Application Gateway and routing them to different backends, you must create a multi-site listener for each host name. By specifying dev.contoso.com as the host name in the new listener, the Application Gateway can correctly route traffic to the dev backend pool without affecting traffic for prod.contoso.com.
- B. Incorrect.
Incorrect. A single-site listener can only have one host name binding. Attempting to add a second domain to the same single-site listener would not properly differentiate traffic for dev.contoso.com from prod.contoso.com, causing potential routing conflicts.
- C. Incorrect.
Incorrect. Path-based routing rules apply to the same domain but different paths (e.g., /images, /api). If you configure '/dev' in a path-based rule, all requests must explicitly use something like prod.contoso.com/dev, which is not your requirement for dev.contoso.com.
- D. Incorrect.
Incorrect. Creating an additional front-end IP address for dev.contoso.com is unnecessary if you're comfortable sharing the same public IP for both environments. You can handle multiple domains on a single IP using multi-site listeners, making an extra IP configuration superfluous.