Questions tagged [dns]

DNS QUESTIONS MUST BE PROGRAMMING RELATED. Use this tag for programming questions related to writing code that interacts with the Domain Name System (DNS); for example, writing code that uses gethostbyname()

Don’t use this tag for questions that aren’t about programming. StackOverflow as a site is only for questions about programming. If you have a DNS-related question about server configuration, DNS configuration, or other non-programming questions, consider instead posting on:

Background information on DNS

The Domain Name System (DNS) is a hierarchical naming system built on a distributed database. It translates domain names meaningful to humans into the IP addresses associated with the networking device. For example: www.stackoverflow.com => 64.34.119.12

One thing that DNS makes possible is changing the IP address while not changing the name. This allows moving the site to another provider, without requiring users to learn anything new. It is also possible to have several different DNS names resolve to the same IP address, and have the same http web server at that IP address handle the different names as different websites.

As already stated, DNS is hierarchical and distributed system. In looking up cs.luc.edu four different DNS servers may be required: for the so-called "DNS root zone", for edu, for luc.edu and cs.luc.edu. Searching hierarchy can be cumbersome, so DNS search results are usually cached locally.

Specification

The concepts of the Domain Name System are explained in RFC1034. The specification and implementation are described in RFC1035.

Reference

Domain Name System on Wikipedia

An Introduction to Computer Networks by Peter L Dordal


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Can I configure a subdomain to point to a specific port on my server

I have an old computer which I converted into a Minecraft server. I have 2 Minecraft servers running simultaneously, one on port 25565 (default) and one on port 25566. I bought the domain something.example and pointed it to my server. Right now, in…
alecwhardy
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Multiple GitHub Pages and custom domains via DNS

I want to have one user page and multiple project pages hosted by GitHub Pages but available under ONE custom domain (with subdomains for each GitHub Pages repository, of course). So my goals are as follows: One user page…
Florian Wolters
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Is it possible to have one (single) character top level domain name?

I'm writing a Regex to validate email. The only one thing confuse me is: Is it possible to have single character for top level domain name? (e.g.: lockevn.c) Background: I knew top level domain name can be from 2 characters to anything (.uk, .us to…
Thach Lockevn
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How do I get the local machine name in C#?

How do I get the local machine name?
Yoann. B
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Linux command line error message: Temporary failure in name resolution

I'm getting error message "Temporary failure in name resolution" when trying to ping a domain name such as a website. When I ping a discrete IP address then ping works normally. ping: google.com: Temporary failure in name resolution This problem…
Nicolai Jacobsen
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Amazon S3: Static Web Sites: Custom Domain or Subdomain

Amazon.com just announced that one can host static web sites in a S3 bucket. I went to their setup page at http://docs.amazonwebservices.com/AmazonS3/latest/dev/index.html?WebsiteHosting.html and created a bucket for my static web site, and it…
Jay Godse
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How to redirect DNS to different ports

TL;DR: DNS resolution of a domain(s) must map to IP:port(s), instead of just IP. Example, sub1.example.com 192.0.2.4:4567 sub2.example.com 192.0.2.4:5678 I CAN modify DNS records. I own the domain "Arboristal.com". I also own all sub domains…
Swordstoo
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DNS redirect domain.example to www.domain.example

I have performed a web search for the question but totally disappointed with the results. The case is to redirect all requests to domain.example to subdomain www.domain.example. So what I have: www.domain.example - main website domain, all client…
Maksim
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DNS caching in Linux

I am confused about DNS caching. I am writing a small forward proxy server and want to use the OS DNS cache on a Linux system. If I understand correctly, there is DNS caching at the browser level. Then there is DNS caching at the OS level (Windows…
agent.smith
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Maximum length of a domain name without the http://www. & .com parts

What is the maximum length of the 'name' part in a domain? I'm referring to the google in http://www.google.com. How long can the google part be without what's before and after it?
Norman
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Why does Microsoft Edge open some local websites, but not others, where the domain name is routed to 127.0.0.1 in hosts file

Like a lot of programmers, I test sites locally. I use the hosts file to map domain names to my local ip (127.0.0.1). I use qualified domain names, usually with a "d" subdomain (for "development"). For example: d.somewebsite.com…
Evan de la Cruz
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Assigning a domain name to localhost for development environment

I am building a website and would not like to reconfigure the website from pointing to http://127.0.0.1 to http://www.example.com. Furthermore, the certificate that I am using is of course made with the proper domain name of www.example.com but my…
fixedpoint
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Using dig to search for SPF records

I am using dig installed on my machine to search for SPF records for a particular domain. Is there a way to search a particular DNS server for the SPF records? For example, will the following work? dig domain.example txt host…
bjtilley
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How do I solve the "server DNS address could not be found" error on Windows 10?

After installing Windows 10, I am continuously getting the "server DNS address could not be found" error. I will be able to use the Internet for 4-5 minutes, and after that for 20-25 min I will get the above error. How do I resolve this issue?
Dixit Singla
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Reverse ip, find domain names on ip address

How and from where websites like this http://www.yougetsignal.com/tools/web-sites-on-web-server/ are getting this information from? How can I develop such tool? Thank you.
Kirzilla
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