How to Capture Packets (PCAP) and Submit to Support
Packet capture guide using Linux tcpdump and Windows Wireshark. Create PCAP files for network analysis, troubleshoot connectivity issues, and submit to support.
Table of Contents
Introduction
Packet capture (PCAP) is the process of recording network traffic. It's used to analyze network issues, connection problems, and attack traffic.
PCAP files contain raw network traffic records. They can be opened and analyzed with tools like Wireshark.
Linux Packet Capture (tcpdump)
Installation
sudo apt-get install tcpdump # Debian/Ubuntu
sudo yum install tcpdump # CentOS/RHEL
Basic Usage
# Capture on all interfaces, specific port
sudo tcpdump --interface any -w capture.pcap -nn port 25565
# Capture from specific IP
sudo tcpdump --interface any -w capture.pcap -nn host 1.2.3.4
# Limited packet count
sudo tcpdump --interface any -w capture.pcap -nn -c 1000 port 25565
Stop capture with CTRL+C.
Adjust capture duration to the time window when the issue occurs. Usually 1-5 minutes is sufficient.
Windows Packet Capture (Wireshark)
- Download from wireshark.org
- Open Wireshark as administrator
- Select the active network interface
- Capture starts automatically
- File → Save As to save as
.pcap
Unfiltered capture can create very large files. Use port or IP filters when possible.
Submitting to Support
- Complete the capture and save the
.pcapfile - Create a support ticket at my.rexe.tr
- Attach the PCAP file
- Include: capture date/time, duration, which service/port, issue description, server IP
Related Articles
SSH Connection Problem: Can't Connect to Server
SSH connection troubleshooting guide: Path.net firewall rules, Default Block, creating a filter rule for SSH port, and step-by-step troubleshooting.
RDP Connection Problem: Can't Connect to Windows Server
RDP connection troubleshooting guide: Path.net firewall rules, Default Block, creating a filter rule for RDP port, and step-by-step troubleshooting.
How to Run an MTR Test and Submit Results to Support
Guide to running MTR network tests with WinMTR and Linux MTR, creating ICMP filter rules, and submitting results to support. Diagnose packet loss and latency.