All posts by Christian Zagrodnick

About Christian Zagrodnick

CEO / CFO Flying Circus

S3 outage: more diversity needed

The latest Amazon S3 outage showed me one thing again: more diversity is better.

Diversity is a current topic that includes social issues like women in tech. However, on a technical basis diversity also is important. It’s known that monocultures are more affected by diseases and other issues. So when half of the internet is using Amazon, a lot goes down if Amazon fails.

Every system will eventually fail. This is true for Amazon, as well as us. The internet is moving fast away from independent, interconnected nodes to an oligopoly. Nobody gets fired for using AWS nowadays. And that’s a problem I think. We need to embrace independent providers for the better of the internet.

Photo by Andrew Fogg.

Elephant in Serengeti

PostgreSQL version migration

Migrating PostgreSQL from one version to another has become pretty easy. Using pg_upgrade it takes a few seconds to upgrade even a 100GiB database. It becomes interesting when you switch platforms, say from 32bit to 64bit, as we are facing it with our switch from Gentoo to NixOS. Our NixOS-based platform is stable enough for customers to use it. Some larger databases benefit especially from larger RAM sizes.

So the question is: How to migrate from 32bit to 64bit with as little downtime as possible?

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Automatic installation of Oracle Java

Our customers at times require Oracle Java for their applications. Our new platform is based on NixOS. As with most Linux distributions, Oracle Java cannot be installed just like that. Oracle’s license prevents redistribution or direct downloading from their servers. NixOS is no exception there.

While manual installation is pretty straightforward on NixOS, ultimately an automated process is what makes operators happy. We use Batou for this.

Continue reading Automatic installation of Oracle Java

Interview with Investforum

investforum-logoOur CEOs Christian Theune and Christian Zagrodnick were interviewed (German only) by Investforum Sachsen-Anhalt. The Investforum is a regional organisation in Saxony Anhalt that helps investors and startups to find each other. The Flying Circus was also attending their events which helped us finding our investor.

In the interview we talk about how this worked and what we can recommend from our experience.

Debugging web application performance with HAProxy – Part 2

Welcome back. In part one, we discussed the basics of reading haproxy logs – today we’ll look further.

My site is slow!

So you notice that your application is not as fast as you’re used to – but why?

The most common reason is, obviously, that your application itself takes a long time to respond to requests, but not always. To find out whether this is true (or whether something else is going on) haproxy has “timers”.

Continue reading Debugging web application performance with HAProxy – Part 2