DE - synthetic transactions

CE ans

Option C and E

A - Adding metrics doesn't necessarily reflect reliability from a user perspective' B - Modifying the code is against the requirement C - Analyzing proxy logs doesn't connect the findings to a user perspective From the request logs, user journeys can be recreated (E) and the replays can be fed to synthetic clients to simulate/replay (D).

1.Based on " without making any engineering changes to it" , exclude A,B at first. 2. Based on following described, https://cloud.google.com/architecture/adopting-slos#choosing_a_measurement_method D & E should be better.

Answer: CE A. Review current application metrics and add new ones as needed. ==> (x) "add new ones" needs engineering changes B. Modify the code to capture additional information for user interaction. ==> (x) "Modify the code" needs engineering changes C. Analyze the web proxy logs only and capture response time of each request. ==> (O) no engineering changes D. Create new synthetic clients to simulate a user journey using the application. => (x) "Create new synthetic client" needs engineering changes. E. Use current and historic Request Logs to trace customer interaction with the application. ==> (O) no engineering changes

D & E - Reliability review using synthetic transactions and customer journeys from logs.

This two option doesn't require engineering changes into the application. Web Proxy logs is a forward proxy thing so it present in client side. others need changes

C& E. C-> a web proxy relays URL requests from clients to a server. Analyzing web proxy logs can give unobtrusive insights into the browsing behavior of users

Selected Answer: DE

C and E should be the correct answer, since the question state that "without making ANY engineering changes"

A&D should be the correct answer: D - Easy/default choice since this doesnt need any changes on the app A - Since the ask is to "measure reliability" - review and add the appropriate SLIs. Option E -tracing is needed only for collecting/troubleshooting latency issues - hence not the correct choice

To me , it looks C & E B & D, need engineering changes and investment, hence I ruled these two out This leaves us with A, C and E - The question is asking for "Need to measure Application Reliability from User perspective without Engineering Changes" - This rules out A, as talks about adding new metric but not stating which one Considering high-traffic web application as "Request Driven Services" - Two of the suggested SLI's are Availability and Latency - C & E to me covers Latency https://cloud.google.com/architecture/adopting-slos?hl=en

A & D is the answer

maybe C,D,E, and it looks like create synthetic client looks like "engineering change", so I choose C and E .

for me it looks like C,E the correct answer. E for sure.

may be A&E as these options may not need any additional engineering efforts