Networking and Unix

TemplateFx v2.37

 June 3rd, 2014Jun 3rd, 2014      

I am pleased to announce the release of Template v2.37 – a scriptable dynamic templating tool that enables you to write configuration templates once and deploy multiple times – never do the same thing twice.

Download links and instructions can be found on the TemplateFx page.


The changes in this release are summarised below:

  • Added initial support for IPv6 to the “ip()” function.
  • Added support for intelligent Redo and Undo buffers for Snippets.
  • Remembers caret position when switching between Snippets.
  • Fixed a Find bug when matching zero-width results using regular expressions.

Feedback welcome as well as suggestions or enhancement requests or general queries!

General IPv6 TemplateFx

The Long Road to IPv6

 September 22nd, 2013Sep 22nd, 2013      

There is a transition happening, albeit slowly, from IPv4 to IPv6, that is going to have an impact, but mostly on online gaming and other peer to peer services. Ever since the introduction of the Internet as we know it today, we have been using public IPv4 addresses to talk to people and to access content online. Unfortunately we have run out of IPv4 addresses as there weren’t enough to go around. An IPv4 address is a 32-bit number which is represented as 4 numbers separated by a dot (e.g. – this provides roughly 4.3 billion addresses. In comparison, an IPv6 address is a 128-bit number which is represented as 8 groups of 4 hexadecimal digits separated by a colon (e.g. 2001:0db8:85a3:0042:1000:8a2e:0370:7334) – this amounts to approximately 48,000 quadrillion addresses (4.8 x 10^28) for each of the seven billion people alive in 2011.


General IPv6 NAT

Cisco IOS: IPv6 Accounting using Flexible Netflow

 September 8th, 2011Sep 8th, 2011        1

I am a big fan of IP Accounting as it enables me to keep long term-ish statistics on a per src/dst prefix basis. I am able to work out my weekly or monthly bandwidth usage and can see how much data each host on my network uses. I can see that I have used a total of 4.7GB in the last 5 days and the majority of that has been towards my Apple TV. A lot of people are probably thinking this is probably achieved better using a more scalable solution like NetFlow, but I like the ability to query this data on-box and not have to use a collector.


General Cisco IPv6