F5 Networks 303 Exam - Topic 4 Question 20 Discussion

Actual exam question for F5 Networks's 303 exam

Question #: 20
Topic #: 4

A web application requires knowledge of the client's true IP address for logging and analysis purposes. Instances of the application that can decode X-Forwarded-For HTTP headers reside in pool_a, while pool_b instances assume the source IP is the true address of the client.

Which iRule provides the proper functionality?

Awhen HTTP_DATA {
if {[HTTP::header exists X-Forwarded-For]}{
pool pool_a
} else {
pool pool_b
}
}

Bwhen HTTP_RESPONSE {
if {[HTTP::header exists X-Forwarded-For]}{
pool pool_a
} else {
pool pool_b
}
}

Cwhen HTTP_REQUEST {
if {[HTTP::header exists X-Forwarded-For]}{
pool pool_a
} else {
pool pool_b
}
}

Dwhen HTTP_OPEN {
if {[HTTP::header exists X-Forwarded-For]}{
pool pool_a
} else {
pool pool_b
}
}

Show Suggested Answer

Suggested Answer: C

by Dannie at Aug 18, 2025, 02:31 AM

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Quentin

4 months ago

Wait, isn't B just wrong? It should be about requests, not responses.

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Marshall

4 months ago

I think A makes more sense, it's about the data.

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Nakisha

4 months ago

Definitely C, that's when the request is made.

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Jina

5 months ago

A is a solid choice, but I lean towards C too.

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Rebecka

5 months ago

I agree with C, but I’m surprised it’s not more obvious!

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Chun

5 months ago

I feel like HTTP_RESPONSE wouldn't be correct because we need the IP before the response is sent, right? So, maybe it's C?

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Tish

5 months ago

I'm a bit confused; I thought HTTP_DATA might be the right choice since it deals with data, but now I'm not so sure.

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Josphine

5 months ago

I think we practiced a similar question, and I recall that HTTP_REQUEST is the right context for checking headers.

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Estrella

6 months ago

I remember we discussed how the X-Forwarded-For header is used to identify the client's IP, but I'm not sure which event to use here.

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Lizette

6 months ago

This is a good one. I think the answer is option C, since we want to check the header during the HTTP_REQUEST event to determine the appropriate pool.

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Tamekia

6 months ago

I'm a bit confused by the different pool options. I'll need to make sure I understand the purpose of each pool and how they relate to the X-Forwarded-For header.

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Belen

6 months ago

Okay, I've got this. The question is asking about logging the client's true IP address, so I'll want to check the header during the request, not the response.

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Eden

6 months ago

Hmm, the key seems to be determining when to check for the X-Forwarded-For header. I'll need to think through the different HTTP events and which one would be most appropriate.

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Leota

7 months ago

This looks like a tricky one. I'll need to carefully read through the question and options to understand the context and determine the right iRule.

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Lenna

8 months ago

I think the correct iRule is option A.

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