> For the complete documentation index, see [llms.txt](https://riteshs4hu.gitbook.io/infosec-notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://riteshs4hu.gitbook.io/infosec-notes/reconnaissance/active-reconnaissance-approach/netwrok-scanning-tools/traceroute.md). # traceroute Traceroute is a network diagnostic tool used to trace the path (route) that data packets take across the internet from a source to a destination, identifying the routers along the way. ### Syntax ```bash traceroute [options] [packet_length] ``` ### Basic Usage * **Trace route to a destination (default UDP method)** ```bash traceroute example.com ``` * **Use ICMP Echo Request instead of UDP** ```bash traceroute -I example.com ``` * **Use TCP SYN packets (default port 80)** ```bash traceroute -T example.com ``` * **Use UDP with a specific destination port (e.g., 53 for DNS)** ```bash traceroute -U -p 53 example.com ``` ### Controlling TTL & Queries * **Set the initial TTL (starting hop)** ```bash traceroute -f 5 example.com ``` (Starts tracing from hop 5 instead of 1.) * **Set the maximum number of hops** ```bash traceroute -m 50 example.com ``` (Stops tracing after 50 hops.) * **Set the number of probes per hop** ```bash traceroute -q 5 example.com ``` (Sends 5 probes instead of the default 3.) ### Output Customization * **Disable hostname resolution (numeric IPs only)** ```bash traceroute -n example.com ``` * **Show AS (Autonomous System) numbers** ```bash traceroute -A example.com ``` * **Increase wait time for each response (default: 5 seconds)** ```bash traceroute -w 10 example.com ``` ### Performance & Routing Options * **Specify a source IP or interface** ```bash traceroute -s 192.168.1.100 example.com ``` ```bash traceroute -i eth0 example.com ``` * **Bypass normal routing and send packets directly** ```bash traceroute -r example.com ``` * **Set a minimum delay between probes** ```bash traceroute -z 5 example.com ``` (Sends probes with a 5-second gap.) ### Advanced Options * **Enable packet fragmentation (or prevent it)** ```bash traceroute -F example.com # Do not fragment ``` * **Trace route using a raw protocol (e.g., DCCP, UDP-Lite)** ```bash traceroute -D example.com # DCCP traceroute -UL example.com # UDP-Lite ``` * **Discover MTU along the path** ```bash traceroute --mtu example.com ``` ### Examples 1. **Basic traceroute with numeric output** ```bash traceroute -n google.com ``` 2. **ICMP-based traceroute** ```bash traceroute -I google.com ``` 3. **TCP-based traceroute on port 443** ```bash traceroute -T -p 443 google.com ``` 4. **Tracing a route with AS number lookups** ```bash traceroute -A google.com ```