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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How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X Lion?

Since setting up my development environments on Mac OS X Lion (brand new macbook air purchased in January 2012), I have noticed that resolving to a virtual host is very slow (around 3 seconds) the first time but after that is fast as long as I…
Adam Gries
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Set up Heroku and GoDaddy?

I am trying to get a domain name I bought through GoDaddy to work with my Heroku hosted site. How do I configure my domain name to work with Heroku?
allegutta
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How to configure heroku application DNS to Godaddy Domain?

I have created a heroku application and wants to give domain to it from godaddy.com. I have configured all three hosts provided by heroku but now I am getting error saying: Heroku | No such app There is no app configured at that hostname. Perhaps…
Arpit Vaishnav
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How do I set up DNS for an apex domain (no www) pointing to a Heroku app?

I already added a custom domain to my Heroku app and it works with www.domain.com. I need to know how to set up the domain without www to resolve to the app, too. Here are my current DNS settings: $TTL 86400 @ IN SOA ns1.first-ns.de.…
mrks
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Creating self signed certificate for domain and subdomains - NET::ERR_CERT_COMMON_NAME_INVALID

I followed this tutorial for creating Signed SSL certificates on Windows for development purposes, and it worked great for one of my domains(I'm using hosts file to simulate dns). Then I figured that I have a lot of subdomains, and that would be a…
Zed
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Mac OSX Lion DNS lookup order

After upgrading to Mac OSX Lion I figured out that /etc/hosts is not looked up in first place for name resolution anymore. This leads to some side effects like: Entries in /etc/hosts are resolved painfully slow You can't not override existing…
Meik
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Network calls fail during image build on corporate network

I'm having a problem building Docker images on my corporate network. I'm just getting started with Docker, so I have the following Dockerfile for a hello-world type app: # DOCKER-VERSION 0.3.4 FROM centos:6.4 # Enable EPEL for Node.js RUN …
dsw88
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Is it ok to remove Google TXT verification records after I've authorized my domain with Google?

For Google Analytics, I had to prove that I owned my domain. I added a TXT record to do this. I also had to prove to Microsoft that I owned my domain by uploading a file (BingSiteAuth.xml) to my site. Now that I'm up and running with Analytics and…
John
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Is www a subdomain?

I recently purchased something.com. When I visit something.com from my browser, I get the index page I uploaded on server. However, if I visit www.something.com, it shows Error 404. So I create a sub-domain named 'www' and upload another index file…
aBhijit
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How to reach docker containers by name instead of IP address?

Is there a way I can reach my docker containers using names instead of ip addresses? I've heard of pipework and I've seen some dns and hostname type options for docker, but I still am unable to piece everything together. Thank you for your time. I'm…
Zhao Li
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Exporting DNS zonefile from Amazon Route 53

I would like to export a DNS zonefile from my Amazon Route 53 setup. Is this possible, or can zonefiles only be created manually? (e.g. through http://www.zonefile.org/?lang=en)
casparjespersen
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How to fix: Domain does not resolve to the GitHub Pages server. Error in Github Pages for custom domain setup with Enforce HTTPS Enabled?

So I am trying to get a custom domain to work with my github pages user site. I have followed pretty much the standard procedure for doing this as follows: (recommended by github here too:…
Atif Ali
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.htaccess rewrite subdomain to directory

Is it possible to use .htaccess to rewrite a sub domain to a directory? Example: http://sub.domain.example/ shows the content of http://domain.example/subdomains/sub/
Erik Djupvik
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How can I set / change DNS using the command-prompt at windows 8

How can I set my DNS settings using the command-prompt or bat file at windows 8 I tried this: netsh interface ip set dns name="Local Area Connection" source=static addr=none but not worked.
Zuhair Taha
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Assigning vhosts to Docker ports

I have a wildcard DNS set up so that all web requests to a custom domain (*.foo) map to the IP address of the Docker host. If I have multiple containers running Apache (or Nginx) instances, each container maps the Apache port (80) to some external…
ringmaster
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