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Comment by Imustaskforhelp | Hacker News Reader

Extremely offtopic but I accidentally pasted the link linuxtoaster.com. (with the dot) and I thought it would lead to my search engine (DDG) or something but then the website opened.

Then I tried opening up google.com. and this works too. I didn't know that websites resolve when you add another additional dot after TLD. This was a really fun coincidence type thing so I wanted to share it with you.

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That's what makes domains true FQDNs :)

I read an interesting blog article on this a while back: https://lacot.org/blog/2024/10/29/the-trailing-dot-in-domain...

This is an interesting rabbit hole I wasn't prepared to jump in. Thanks for sharing the article, the world does work in strange coincidences indeed.

Have given a glance through it but I am also bookmarking to read it later once I get more free. Thanks for sharing it!

From the article:

> Wait, what? I can put a dot at the end of my domain names?

This was exactly how I felt at that moment :) The article has started pretty nicely.

The final dot indicates that the name is fully qualified. Without a final dot, DNS looks up the name and if that fails, it tries again appending each of the suffixes specified in "search" in /etc/resolv.conf.

I got tripped by this once - a tester at work accidentally added a trailing . to a dev site URL and everything was broken... because the CORS code didn't account for a trailing . in the URL.

IIRC domains names read from the right and the first dot is omitted. It's actually

com. example.com. subdomain.example.com.

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