Mastering Linux Network Diagnostics with the mtr Command

Overview

MTR (My Traceroute) combines the functionality of traceroute and ping to probe network paths, display each hop, and report round‑trip times (RTT) and packet loss in real time. It is valuable for network engineers and system administrators diagnosing latency or loss issues.

Key Features

Dynamic routing display : Continuously updates hop information instead of a single snapshot.

Packet type selection : Sends UDP by default, but can use ICMP Echo requests.

Latency and loss reporting : Shows RTT, loss percentage, and other statistics per hop.

Filtering and logging : Allows filters for specific routers and can save results to log files.

Protocol flexibility : Works over different protocols and ports.

Basic Usage

Syntax

mtr <target‑IP‑or‑hostname>

Help

mtr --help

Common Options

-r

: Report mode – send a fixed number of packets and then stop (e.g., -r 10). -c: Continuous mode – send packets indefinitely. -i: Interval between packets in seconds (default 1 s). -s: Packet size in bytes (default 50 B). -u: Use UDP instead of ICMP. -P: Set ICMP type (default type 8).

Output Explanation

The typical MTR table includes:

Host : IP address or hostname of the hop.

Loss% : Packet loss percentage at that hop.

Snt : Number of packets sent.

Last : RTT of the most recent packet.

Avg : Average RTT.

Best : Minimum RTT.

Wrst : Maximum RTT.

StDev : Standard deviation of RTT.

Command Examples

Basic test to www.example.com: mtr www.example.com Report mode (fixed 10 packets): mtr -r 10 www.example.com Set 1‑second interval between pings: mtr -i 1 www.example.com Show only IP addresses (no DNS lookup): mtr -n 8.8.8.8 Specify packet size (e.g., 1500 B) to test MTU: mtr -s 1500 www.example.com Force UDP probing: mtr -u www.example.com Save output to a file for later analysis: mtr www.example.com > mtr_output.txt Batch mode for parsable output: mtr -b www.example.com > output.txt Combine options (e.g., packet size 100 B, port 80):

mtr -s 100 -p 80 www.example.com

Installation

MTR is available in the default repositories of most Linux distributions.

Debian/Ubuntu: sudo apt-get install mtr Red Hat/CentOS: sudo yum install mtr After installation, running mtr --help confirms the tool is ready.

Sample Output