IOS:Open Source Lab DNS and IP Addressing

A number of Cisco Bloggers have talked about making labs available for others to use. However, part of what will be needed is some conventions to make these labs work for the largest number of people.

Following Ivan Pepelnjak posting on Private Domain Names, and an earlier posting that I made on Reserved IP Address for Testing I believe we have perfect combination for DNS and IP addresses for building live test environments, that will work for Open Source lab scenarios.

Reserved Domain Names

From RFC2606 on Reserved Domain Names:

To safely satisfy these needs, four domain names are reserved as listed and described below.

.test
.example
.invalid
.localhost

“.test” is recommended for use in testing of current or new DNS related code.

“.example” is recommended for use in documentation or as examples.

IP Range Allocated for Testing

From RFC3330:
198.18.0.0/15 – This block has been allocated for use in benchmark tests of network interconnect devices. Its use is documented in [RFC 2544].

Use in LAB networks

When I build a test network in a Corporate Networks, I am looking for an Address range that will never have an impact on the live system. And if some sort of configuration accident occurs where traffic is introduced into the corporate system, I need to be able to clearly identify where this traffic is coming from. Unique IP addresses is a solution to this.

The use of a DNS naming convention that clearly identifies test traffic, and also the use of clearly defined range for test IP addresses. The use of .test extensions would allow for the creation of the a DNS range that is unique to a test environment, and be readily identified.

Widespread Use

So here is a request to everyone, if you plan to write a lab or develop a testing plan or publish a configuration, consider using these DNS names and IP addresses. This could produce some consistency in our lab scenarios, and make them portable into our corporate test environments, if you like, a first step to an open source look at network labs.

Please leave comments below to show support either for or against. If there is sufficient interest, I have a forum prepared for better discussion. I look forward to hearing from you.

Other posts in the series

  1. Cisco IOS CLI Regex: sh ip bgp in
  2. IOS CLI Tip: More accurate pipe commands
  3. Cisco Nexus NXOS and Fixing broken “switchto” syntax with alias
  4. show ip eigrp topology all
  5. Cisco IOS CLI Shortcuts
  6. The poor man's IOS Traffic Generator
  7. IOS: "terminal monitor" on, off - logging to your terminal
  8. IOS: Console, Terminal, Monitor, VTY - what is what ?
  9. IOS: Clearing an interface configuration
  10. IOS: Setting Terminal Window Length
  11. IOS CLI: show run linenum
  12. IOS: Setting the TCP timeout on IOS
  13. IOS: enable and .... disable ?
  14. IOS: Reverse SSH console access - Part 2
  15. IOS:Open Source Lab DNS and IP addressing (This post)
  16. IOS: Reverse SSH console access
  17. ip tcp timestamp
  18. Cisco ASA and IOS command tip - test aaa-server
About Greg Ferro

Greg Ferro is a Network Engineer/Architect, mostly focussed on Data Centre, Security Infrastructure, and recently Virtualization. He has over 20 years in IT, in wide range of employers working as a freelance consultant including Finance, Service Providers and Online Companies. He is CCIE#6920 and has a few ideas about the world, but not enough to really count.

He is a host on the Packet Pushers Podcast, blogger at EtherealMind.com and on Twitter @etherealmind and Google Plus

  • http://www.globalconfig.net/ Brandon Carroll

    I think its a great Idea. Why make things harder than we have to. A Little community goes a long way.