Kalle Happonen

Yubikey, ibikey, let'sallbikey!

SSH is one of the most important tools I use. It has tons of cool features for the power user. First off any serious use needs SSH keys and ssh-agent to go with that. Socks proxy forwarding is super powerful, as is SSH mutlihop. GitHub works nicely with SSH, and Ansible builds on SSH. And when you use Ansible, you probably want to throw in . . .

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November 14, 2016


or The Blog Post I Wish I had Read a Year Ago

We've been working with OpenStack for a while now. The first version we started playing around with was Diablo in 2011. After some time of working on proof-of-concepts, and getting our hands dirty, we were tasked with setting up a production platform.

There are tons of information about the technical stuff you need to do when . . .

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November 06, 2016


I usually write an upgrade report on our OpenStack version upgrades. We recently upgraded from Juno to Liberty. I haven't gotten to writing how it went, partly because it went so smoothly.

Disclaimer: The preparation and work behind this was mostly done by others than yours truly. Architecture-wise we still run monolithic . . .

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October 24, 2016

Phish Vendors

We run a lot of servers. Sometimes they break, and you have to involve the vendor. I thought I'd write about a severe security issue with the support cases. This is probably well known for most people dealing with vendors, but I don't think there's been enough discussion about it.

The problem

Let's say you . . .

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September 08, 2016

The I/O intensifies

A sought after feature in our cloud has been something to support Hadoop/Spark functionality. So far our I/O performance hasn't been anything to write home (or to the internet) about, but let's hope that will change soon.

What we basically want to do is provide high IOPS capable temporary data processing VMs. On the hardware . . .

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June 09, 2016

Spread 'em!

Especially if you're packin'!

Generic disclaimer: OpenStack Juno (but up to Mitaka I haven't seen a way to do this).
Specific disclaimer: The code for this was written by my colleague Risto Laurikainen, and the credit goes to him.

Let's just jump right into it. We have a small scheduling problem in OpenStack Nova. To understand it, let's explain . . .

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May 09, 2016

Of Cattle and Pets

And Bessie the friendly cow, and that ratty cat you never really liked.

I have been thinking a lot about cattle and pets lately (in the IT sense). If you are not aware of the concept, it's something that Randy Bias (from EMC/Cloudscaling) coined and the admins at CERN made popular. It basically says, you can treat your servers like pets or like cattle.

Slide from CERN presentation

It's a great simple way to think . . .

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March 28, 2016


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