212-89 Network Incidents Practice Question
You are investigating a compromised Linux host. Using 'tcpdump' to capture traffic on interface eth0 to analyze C2 communication on port 443, which command is most efficient for saving the output to a file for later analysis in Wireshark?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
tcpdump -i eth0 port 443 -w capture.pcap
The -w flag is used in tcpdump to write raw packets to a .pcap file.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
tcpdump -c eth0 port 443
Why it's wrong here
-c is used to limit the number of packets captured.
- ✗
tcpdump -i eth0 port 443 > capture.txt
Why it's wrong here
Redirecting to a text file corrupts the binary packet data, making it unreadable by Wireshark.
- ✗
tcpdump -r capture.pcap port 443
Why it's wrong here
-r is for reading files, not capturing.
- ✓
tcpdump -i eth0 port 443 -w capture.pcap
Why this is correct
The -w flag correctly writes the captured traffic to a file.
About these practice questions
One of 206 original 212-89 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official EC-Council exam blueprint
This 212-89 practice question is part of Courseiva's free EC-Council certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 212-89 exam.