Category Archives: Software

Hosting services on Google Kubernetes Engine

Posted on May 28, 2022 by erik

This post explains how to host services on Google Compute Engine, parts of this are applicable to regular (non-GKE) Kubernetes clusters as well. This post will cover: allowing multiple services to be deployed in different namespaces allowing multiple (sub)domains to … Continue reading →

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Setting up up a deep learning box

Posted on April 30, 2018 by erik

After doing a number of courses on machine learning I now have some overview of what is available and how it all works. So now it is getting time to start doing some work from start to finish myself. To … Continue reading →

Posted in Data Science, Devops/Linux, Fun, Software | Leave a comment

Why finalizers are really bad

Posted on November 24, 2013 by erik

It is more or less common knowledge that using finalize functions in java is bad. For one, you are depending on garbage collection for cleanup and there is no guarantee when the finalizer will be called. Further there is also … Continue reading →

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Encrypting an existing Centos install (2)

Posted on October 22, 2013 by erik

In a previous post, I described how to encrypt an existing Centos install that approach was based on find out how LUKS worked and then creating a storage logical volume that was encrypted with then logical volumes on top of … Continue reading →

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Encrypting an existing Centos install

Posted on October 19, 2013 by erik

Edit: Meanwhile I have found a better way to migrate an existing centos unencrypted install to a fully encrypted install with /boot as the only unencrypted disk space. This solution is much preferred over the one described in this post. … Continue reading →

Posted in Devops/Linux, Java, Software | 1 Comment

Creating a USB install for Centos 6.4

Posted on May 9, 2013 by erik

The days of rotating disks for storing information and in particular for installing OSes are nearing their end. Why rely on something with rotating parts for storing data in the 21st century? Unfortunately, not every software vendor has caught up … Continue reading →

Posted in Devops/Linux, Software | 4 Comments

Java from the trenches: improving reliability

Posted on October 13, 2012 by erik

Java and the JVM are great things. In contrast to writing native code, making a mistake in your Java code will not (or should not) crash the virtual machine. However, in my new position working for a SAAS company I … Continue reading →

Posted in Devops/Linux, Java, Software | 1 Comment

Why do developers write instead of reuse?

Posted on August 5, 2012 by erik

I am frequently amazed at the amount of software that is being written instead of simply looking around and reusing what’s already available. In practice I have seen a lot of reasons for this: Our problems are unique: The misconception … Continue reading →

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Nested Logical Volume Management for VMs

Posted on November 30, 2011 by erik

Towards a more consistent virtual machine setup using nested logical volume management. I.e. the host/hypervisor allocates storage for virtual machines using logical volume management. The virtual machine itself partitions these virtual disks and uses logical volume management again to simplify management. This blog describes how I migrated and existing VM to use this approach as well.
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Improvements to Snapshot Backup Scripts

Posted on August 11, 2011 by erik

The snapshot scripts that I blogged about earlier have undergone a number of important changes. I had been having a lot of problems with the cleanup of snapshot volumes and with the deletion of the old backup logical volumes. This … Continue reading →

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