Practicalweb Ltd

Technical information on this site may be out of date : no updates since 2015

First Steps with Ansible and Docker

February 18, 2015 , posted under Ansible Docker devops

I’ve been using puppet and vagrant for a while, due to client choices we’re switching to ansible which I’m less familiar with - and Docker has been on my to learn list for a while.

I love vagrant - being able to bring up a VM locally that matches the production servers to a good degree is just brilliant, and being able to repeat deploys is invaluable in testing process.

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November 19, 2014 , posted under grafana graphite graphing devops metrics

I’ve been playing with some new toys.

What motivated me was a desire to be better able to interpret load test data and performance metrics.

I love graphs, for me the visualisation they provide allows me to recognise patterns and figure out cause/effects massively faster than any other way.

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Developing for Ops

October 14, 2014 , posted under debugging devops bugs

We often work on large websites with strict change control practices and scheduled release cycles. Sometimes we also hand over the systems to the client for production and don’t have direct access ourselves.

Some bugs have a nasty habit of only occurring in production, this may be due to high load, odd/old browsers, changes in data, or just because test scenarios don’t cover every eventuality.

What this means is that when we have a bug in production we can only understand it through the error logging we have already built into the system. If we need to put in place additional logging we usually lose the chance of actually fixing the bug for another release cycle.

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Satellite vs Puppet

November 20, 2012 , posted under puppet satellite spacewalk configuration management devops

I’ve been using Puppet for a little while and am now working on a project that will be using RedHat’s Satellite (the upstream project is Spacewalk).

I haven’t really used puppet in anger on production systems yet, I’m referring to the open source edition of Puppet, and have only read about Satellite, but I didn’t find much comparison out there so thought it worth writing up what I’ve found.

They key differences that strike me are

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