F5 Networks 301b Exam - Topic 2 Question 120 Discussion

Actual exam question for F5 Networks's 301b exam

Question #: 120
Topic #: 2

-- Exhibit --

Refer to the exhibit.

A company uses a complex piece of client software that connects to one or more virtual servers (VS) hosted on an LTM device. The client software is experiencing issues. An LTM Specialist is tasked with finding the cause of the problem.

The LTM Specialist has the tcpdump extract and knows the client software has at least one connection to a VS on port 1990. However, when a tcpdump runs on the internal VLAN, there is no record of port 1990 in the tcpdump.

Why is there no record of port 1990 in the tcpdump?

AThe LTM device drops the connection.

BPort 1990 is a well-known port, so its use is restricted.

CThe LTM device performs a Port Address Translation (PAT).

DThe LTM device performs a Network Address Translation (NAT).

Show Suggested Answer

Suggested Answer: C

by Eleni at Jan 05, 2026, 05:16 AM

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Lawana

16 hours ago

I feel like option C makes sense. PAT could be hiding the port.

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Bettina

6 days ago

I think it's option A. The LTM device might be dropping the connection.

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Lindsey

11 days ago

Definitely a connection drop, I’ve seen that happen before.

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Doyle

16 days ago

Port 1990 is not a well-known port, so that can't be it.

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Edna

21 days ago

Surprised there's no mention of PAT in the options!

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Tien

27 days ago

I think it’s more likely a NAT issue.

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Malinda

1 month ago

The tcpdump not showing port 1990 could mean the LTM is dropping it.

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Elli

1 month ago

I bet the LTM Specialist is scratching their head, trying to figure out where that port went.

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Joni

2 months ago

Haha, the LTM device is like a magician, making the port disappear!

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Werner

2 months ago

D) The LTM device performs a Network Address Translation (NAT).

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Isabelle

2 months ago

C) The LTM device performs a Port Address Translation (PAT).

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Elbert

2 months ago

I feel like the answer might be related to how the LTM handles traffic. Maybe it's dropping the connection or doing something with the addresses?

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Vashti

3 months ago

I'm a bit confused about the difference between NAT and PAT. Could either of those be the reason for not seeing port 1990 in the tcpdump?

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Solange

3 months ago

I think I saw a similar question about tcpdump and port visibility in practice tests. If the port isn't showing, it might be because the LTM is dropping the connection, right?

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Walton

3 months ago

I remember studying NAT and PAT, but I'm not entirely sure how they apply here. Could it be that the LTM is using NAT?

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Ellen

3 months ago

I'm a bit confused on the difference between NAT and PAT. I'll need to review those concepts before deciding on the answer.

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Margurite

3 months ago

I'm leaning towards C) Port Address Translation (PAT). That would explain why the original port 1990 isn't visible in the tcpdump.

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Lea

3 months ago

Okay, let me think this through step-by-step. The client software is connecting to a virtual server on port 1990, but that port isn't showing up in the tcpdump. The answer has to be related to address translation on the LTM device.

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Franchesca

4 months ago

Hmm, no record of port 1990 in the tcpdump? That's really puzzling. I'll have to consider if the LTM device is doing some kind of address translation.

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Murray

4 months ago

This seems like a tricky one. I'll need to carefully review the exhibit and think through the different translation options.

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