Creating minimal Docker images from dynamically linked ELF binaries

Thu 05 February 2015 by Lars Kellogg-Stedman Tags docker

In this post, we'll look at a method for building minimal Docker images for dynamically linked ELF binaries, and then at a tool for automating this process.

It is tempting, when creating a simple Docker image, to start with one of the images provided by the major distributions. For example …

read more

Filtering libvirt XML in Nova

Thu 05 February 2015 by Lars Kellogg-Stedman Tags openstack nova

I saw a request from a customer float by the other day regarding the ability to filter the XML used to create Nova instances in libvirt. The customer effectively wanted to blacklist a variety of devices (and device types). The consensus seems to be "you can't do this right now …

read more

Docker vs. PrivateTmp

Sun 18 January 2015 by Lars Kellogg-Stedman Tags docker systemd namespaces

While working with Docker the other day, I ran into an undesirable interaction between Docker and systemd services that utilize the PrivateTmp directive.

The PrivateTmp directive, if true, "sets up a new file system namespace for the executed processes and mounts private /tmp and /var/tmp directories inside it that …

read more

Running nova-libvirt and nova-docker on the same host

Sat 17 January 2015 by Lars Kellogg-Stedman Tags openstack docker

I regularly use OpenStack on my laptop with libvirt as my hypervisor. I was interested in experimenting with recent versions of the nova-docker driver, but I didn't have a spare system available on which to run the driver, and I use my regular nova-compute service often enough that I didn't …

read more

Building a minimal web server for testing Kubernetes

Sun 04 January 2015 by Lars Kellogg-Stedman Tags docker kubernetes

I have recently been doing some work with Kubernetes, and wanted to put together a minimal image with which I could test service and pod deployment. Size in this case was critical: I wanted something that would download quickly when initially deployed, because I am often setting up and tearing …

read more