What is a Traceroute? (free lookup tool)

Free DNS traceroute lookup tool — what is a traceroute?

Anyone in the DNS world knows there’s a lot more to the internet than meets the eye. For the end user, it appears as if they type something into a web browser-and poof-they are where they want to be. What is really going on is a series of actions between nameservers based on many different predefined rules and configurations. For domains to have that “magical” effect, DNS must be configured correctly. That is why diagnostic tools are so important in this industry. In this resource, you’ll learn all about traceroute-what it is, how it works, and why it’s important for DNS and network diagnostics.

Traceroute Explained

A traceroute maps the path data packets take from start to finish. In other words, it tracks data movement over the internet. Once done, it delivers a report containing round trip times (RTT) for each hop and the IP addresses of each router pinged during the journey. Traceroutes also reveal points of failure. With all the working parts of DNS, knowing how and where data travels is key to diagnosing delays or connectivity issues between devices.

: For a more detailed explanation of DNS, watch our DNS Explained video, which breaks it down in a fun, easy to understand way.

What is a Packet?

What Is a Hop?

How Does a Traceroute Work?

A traceroute identifies routers or servers hop by hop. Packets are sent with a TTL of one. Since the receiving server decrements the TTL by one automatically, it drops it to zero and notifies the source. When the source is notified of the packet drop, it also receives the identity of the router. The next packet is sent with a TTL of two. The first server decreases the TTL to one and passes it on to the next link in the chain. This process repeats incrementally until the final destination or max number of hops is reached.

Traceroute tool — grid example
Traceroute tool — grid example

Traceroute Tool

Here is an example of the line graph and data table from Constellix’s Traceroute Tool.

ns lookup cheat sheet
ns lookup cheat sheet

: Check out our nslookup cheat sheet for Windows for helpful DNS commands for troubleshooting.

Traceroute Command

Here is an example of how results would look using a command line utility. This example is from Windows Command Prompt and includes a max hop command.

How to Read a Traceroute

Routers, Switches, Packets and FramesHow Does a Traceroute Work?

In the data table of Contellix’s tool and results given in the Windows Command Prompt above, the first column is the number of hops, the middle columns reflect the speed of the hops, and the last column shows the router/server’s identity.

Traceroute Wrap Up

If you found this useful, why not share it? If there’s a topic you’d like to know more about, reach out and let me know. I can never talk about DNS enough!

Liked this? You might find this helpful:

Originally published at https://constellix.com.

Constellix is a traffic management suite offering advanced DNS hosting and network monitoring services. Start optimizing your online performance today!