🔍 Perform MTR/Traceroute Diagnosis
This guide will teach you how to use MTR (My Traceroute) and Traceroute to diagnose network connectivity issues, identify latency points, and analyze the quality of your network connection.
📋 Prerequisites
- A VPS server with root or sudo access
- An active SSH connection
- Ubuntu/Debian (commands are adapted for these distributions)
🔧 Installation
Install Traceroute (basic tool)
# On Ubuntu/Debian sudo apt update sudo apt install traceroute -y
Install MTR (advanced tool)
MTR combines the functionalities of ping and traceroute into a single powerful tool.
# On Ubuntu/Debian sudo apt update sudo apt install mtr-tiny -y # For the full version with graphical interface (optional) sudo apt install mtr -y
Verify Installation
# Verify that traceroute is installed traceroute --version # Verify that MTR is installed mtr --version
🛠️ Using Traceroute
Basic Command
# Traceroute to a destination traceroute google.com # Traceroute to an IP traceroute 8.8.8.8 # Limit the number of hops (default 30) traceroute -m 20 google.com # Specify timeout in seconds traceroute -w 5 google.com
Useful Options
# Use UDP (default) traceroute -U google.com # Use TCP (more reliable) traceroute -T google.com # Use ICMP (like ping) traceroute -I google.com # Don't resolve DNS names (faster) traceroute -n google.com
Example Output
traceroute to google.com (142.250.185.14), 30 hops max, 60 byte packets
1 10.0.0.1 (10.0.0.1) 0.123 ms 0.089 ms 0.067 ms
2 192.168.1.1 (192.168.1.1) 5.234 ms 5.189 ms 5.145 ms
3 * * *
4 8.8.8.8 (8.8.8.8) 12.456 ms 12.389 ms 12.334 ms
...
🚀 Using MTR (Recommended)
MTR is more powerful because it sends packets continuously and calculates statistics in real-time.
Basic Command
# MTR in interactive mode (recommended) mtr google.com # MTR with report (non-interactive) mtr --report google.com # MTR with 10 test packets mtr --report --report-cycles 10 google.com # MTR to an IP mtr --report 8.8.8.8
Advanced Options
# Specify the number of packets to send mtr --report --report-cycles 50 google.com # Use TCP instead of ICMP mtr --tcp --port 80 google.com # Use UDP mtr --udp --port 53 8.8.8.8 # Don't resolve DNS names mtr --no-dns google.com # Interval between packets (in seconds) mtr --interval 2 google.com # Packet size (in bytes) mtr --psize 64 google.com
MTR Interactive Mode
When you launch mtr without the --report option, you enter interactive mode:
- d : Show/hide detailed statistics
- n : Enable/disable DNS mode (name resolution)
- r : Reset statistics
- s : Change packet size
- j : Change interval between packets
- q : Quit MTR
📊 Interpreting Results
Normal Latency
- < 50 ms : Excellent, local network or very close
- 50-100 ms : Good, regional connection
- 100-200 ms : Acceptable, intercontinental connection
- > 200 ms : High, may cause problems
Packet Loss
- 0% : Perfect
- < 1% : Normal for an Internet connection
- 1-5% : Acceptable but may cause problems
- > 5% : Problematic, investigation required
Meaning of Asterisks (*)
In traceroute, a * means:
- A single * instead of a time : The router did not respond to that specific packet
- *Three consecutive 's : The router did not respond at all (timeout or firewall filter)
🎯 Use Cases
Diagnosing High Latency
# Test to Google DNS mtr --report --report-cycles 30 8.8.8.8 # Test to Cloudflare DNS mtr --report --report-cycles 30 1.1.1.1 # Identify the problematic hop mtr --report --report-cycles 50 your-domain.com
Diagnosing Packet Loss
# Test with TCP to bypass ICMP filters mtr --tcp --port 443 --report --report-cycles 50 google.com # Test to a specific server mtr --report --report-cycles 100 your-server.com
Test from Your VPS to Your Location
# Test to your public IP address # Get your public IP first curl ifconfig.me # Then test from your VPS mtr --report --report-cycles 30 YOUR_PUBLIC_IP
🔍 Troubleshooting Common Problems
Problem: High Latency on a Specific Hop
If you see high latency on an intermediate hop:
# Test with different protocols mtr --tcp --port 443 --report google.com mtr --udp --port 53 --report 8.8.8.8 mtr --report google.com
Important: High latency on an intermediate hop may be normal if that router doesn't respond quickly to diagnostic requests, but the final latency remains good.
Problem: Significant Packet Loss
If you see high packet loss:
# Test with more packets to confirm mtr --report --report-cycles 100 destination.com # Test with TCP if ICMP is filtered mtr --tcp --port 80 --report --report-cycles 50 destination.com
Warning: If packet loss appears on all hops, the problem is likely on your VPS or your local connection. If it appears only on a specific hop, the problem is on the network between your VPS and the destination.
Problem: Repeated Timeouts
# Increase timeout mtr --timeout 10 --report destination.com # Test with different protocols mtr --tcp --port 443 --timeout 10 --report destination.com
📝 Useful Commands
Complete Diagnostic Script
Create a script to test multiple destinations:
#!/bin/bash echo "=== MTR Test to Google DNS ===" mtr --report --report-cycles 30 8.8.8.8 echo -e "\n=== MTR Test to Cloudflare DNS ===" mtr --report --report-cycles 30 1.1.1.1 echo -e "\n=== MTR Test to your domain ===" mtr --report --report-cycles 30 your-domain.com
Save Results
# Save report to a file mtr --report --report-cycles 30 google.com > mtr-report-$(date +%Y%m%d).txt # With CSV format mtr --report --report-cycles 30 --csv google.com > mtr-report.csv
✅ Best Practices
- Use MTR rather than traceroute : MTR provides more complete statistics
- Test multiple destinations : Compare results to different servers
- Run multiple tests : Networks can vary, run multiple tests at different times
- Use TCP if ICMP is filtered : Some routers filter ICMP but not TCP
- Interpret results correctly : High latency on an intermediate hop is not always a problem if the final latency is good
🆘 Troubleshooting
MTR Doesn't Display Correctly
# If MTR doesn't work in interactive mode, use report mode mtr --report destination.com # Check MTR version mtr --version
Error "mtr: command not found"
# Reinstall MTR sudo apt update sudo apt install mtr-tiny -y # Or install the full version sudo apt install mtr -y
All Results Show Asterisks
If all hops show *, it may mean:
# Your firewall is blocking ICMP # Test with TCP instead mtr --tcp --port 443 --report destination.com # Check firewall rules sudo ufw status sudo iptables -L
📚 Additional Resources
❓ Frequently Asked Questions
Q: What is the difference between Traceroute and MTR?
A: Traceroute sends a few packets and displays results. MTR sends packets continuously and calculates statistics in real-time, which is more useful for diagnosis.
Q: Why do some hops show asterisks?
A: This means the router did not respond. This can be due to a firewall filter, router configuration, or simply that the router doesn't respond to diagnostic requests.
Q: Should I worry about high latency on an intermediate hop?
A: Not necessarily. If the final latency to the destination is good, high latency on an intermediate hop may be normal. It's the final latency that really matters.
Q: How do I interpret packet loss in MTR?
A: Packet loss < 1% is normal. Between 1-5%, it's acceptable but may cause problems. Beyond 5%, it's problematic and requires investigation.