Unused Domain Name and IP Addresses for Documentation

When writing documentation or blog posts it would be nice to include domain references which don’t link to real websites.

Fortunately the people who organised the domain DNS references set aside some domains specifically for this.

The domains won’t be made available and are to be kept purely for documentation.

There’s a document detailing Reserved Top Level DNS Names.

Of particular interest is the use of the following in documentation

  • example.com
  • example.net
  • example.org
  • .example

Well that’s the domain names sorted. What about IP addresses?

Yes, these have been thought about too.

There’s 3 series of the older ipv4 address blocks kept aside for this. Details are given in the document IPv4 Address Blocks Reserved for Documentation.

The address blocks available are:

  • 192.0.2.0/24 (TEST-NET-1)
  • 198.51.100.0/24 (TEST-NET-2)
  • 203.0.113.0/24 (TEST-NET-3)

And there’s the one for ipv6, covered by the document IPv6 Address Prefix Reserved for Documentation.

For ipv6 there’s a reserved prefix, given as 2001:DB8::/32