What is MTR and How to Use It for Network Diagnostics

When troubleshooting network issues, system administrators and network engineers need tools that provide more than a simple "is it reachable?" answer. MTR (My Traceroute) is one of the most powerful diagnostic tools available, combining the functionality of traceroute and ping into a single, real-time interface.

What Does MTR Do?

MTR continuously sends probe packets to a destination and displays the results for every hop along the network path. Unlike a standard traceroute that runs once and exits, MTR keeps running, collecting statistics over time. This makes it invaluable for identifying intermittent packet loss and latency spikes that a single-run traceroute would miss.

Each row in MTR output represents a router (hop) between your device and the destination. For every hop, MTR shows:

• Loss% — the percentage of packets that were dropped at this hop
• Snt — the number of packets sent
• Last — the round-trip time of the most recent packet
• Avg — the average round-trip time across all packets
• Best / Wrst — the minimum and maximum round-trip times observed
• StDev — the standard deviation, indicating how consistent the latency is

How to Run MTR

On most Linux distributions, MTR is available through the package manager. On macOS, you can install it via Homebrew with brew install mtr. A basic MTR command looks like this:

mtr example.com

This opens an interactive view that continuously updates. For a report-style output that runs a fixed number of cycles, use:

mtr --report --report-cycles 100 example.com

Reading MTR Results

The key to reading MTR output is understanding where packet loss actually occurs. If you see loss at hop 5 but not at hops 6 through 10, the loss at hop 5 is likely due to ICMP rate limiting on that router — not actual packet loss. The router is deprioritizing responses to probe packets while still forwarding real traffic normally.

True packet loss is indicated when the loss percentage persists from a specific hop all the way through to the destination. For example, if hops 7 through 12 all show 15% loss, the problem likely originates at hop 7.

MTR vs. Standard Traceroute

Standard traceroute gives you a single snapshot. MTR gives you a movie. Over dozens or hundreds of probe cycles, patterns emerge: a router that occasionally drops packets, a path that shows jitter during peak hours, or a hop where latency suddenly doubles. These patterns are invisible to a one-time traceroute.

Practical Use Cases

MTR is particularly useful for:

• Reporting issues to your ISP — an MTR report provides concrete evidence of where the problem is
• Diagnosing VPN performance — see which hops add the most latency in your tunnel path
• Monitoring server connectivity — run periodic MTR reports to track route quality over time
• Comparing network paths — run MTR from different source locations to see how routing differs

Tools like TraceMapper take MTR output further by mapping each hop on a world map, adding geolocation, ASN data, and visual latency indicators — turning raw numbers into actionable insights.