How to read traceroute output?

To read a traceroute output, follow these steps:

1. Identify the Header: The first line usually contains the command used and the destination IP or hostname.

2. Examine Each Hop:

   • Hop Number: The first column shows the hop number, starting from 1.
   • IP Address: The second column displays the IP address of the router or device at that hop.
   • Response Times: The next columns show the round-trip time (RTT) for packets sent to that hop. Typically, three times are displayed, representing three packets sent.
   • Hostname: If available, the hostname of the router may be shown next to the IP address.

3. Analyze Response Times:

   • Low Times: Indicates a fast response, suggesting a healthy connection.
   • High Times: Indicates potential delays or issues.
   • Asterisks (*): If you see asterisks instead of times, it means that the request timed out, indicating a possible issue at that hop.

4. Final Destination: The last line usually shows the destination IP address and may include the hostname.

Example Output:

traceroute to example.com (93.184.216.34), 30 hops max, 60 byte packets
 1  192.168.1.1  1.123 ms  1.234 ms  1.345 ms
 2  10.0.0.1  5.678 ms  5.789 ms  5.890 ms
 3  203.0.113.1  10.123 ms  10.234 ms  10.345 ms
 4  93.184.216.34  15.678 ms  15.789 ms  15.890 ms

In this example:

• The first hop is your local router (192.168.1.1).
• The second hop is another router (10.0.0.1).
• The final hop reaches the destination (93.184.216.34) with response times indicating the latency at each step.