Tag: virtualization

10 things to avoid in Docker containers

10 things to avoid in Docker containers provides a handy reminder of what NOT to do when building Docker containers.  Read the full article for details and explanations.  For a brief summary, here are the 10 things:

  1. Don’t store data in containers
  2. Don’t ship your application in two pieces
  3. Don’t create large images
  4. Don’t use a single layer image
  5. Don’t create images from running containers
  6. Don’t use only the “latest” tag
  7. Don’t run more than one process in a single container
  8. Don’t store credentials in the image. Use environment variables
  9. Don’t run processes as a root user
  10. Don’t rely on IP addresses

BitBucket Pipelines and Docker for PHP Developers

I’ve been meaning to look into Docker for a long while now.  But, as always, time is the issue.  In the last couple of days though I’ve been integrating BitBucket Pipelines into our workflow.  BitBucket Pipelines is a continuous integration solution, which runs your project tests in a Docker container.  So, naturally, I had to get a better idea of how the whole thing works.

“Docker for PHP Developers” article was super useful.  Even though it wasn’t immediately applicable to BitBucket Pipelines, as they don’t currently support multiple containers – everything has to run within a single container.

The default BitBucket Pipelines configuration suggests the phpunit/phpunit image.  If you want to run PHPUnit tests only, that works fine.  But if you want to have a full blown Nginx and MySQL setup for extra bits (UI tests, integration tests, etc), then you might find smartapps/bitbucket-pipelines-php-mysql image much more useful.  Here’s the full bitbucket-pipelines.yml file that I’ve ended up with.

StackOverflow: Docker vs. Vagrant, with project authors’ comments

There is this discussion over at StackOverflow: Should I use Vagrant or Docker for creating an isolated environment? It attracted the attention of the authors of both projects (as well as many other smart people).  Read the whole thing for interesting insights into what’s there now and what’s coming.  If you’d rather have a summary, here it is:

The short answer is that if you want to manage machines, you should use Vagrant. And if you want to build and run applications environments, you should use Docker.

Serverlessconf 2016 – New York City: a personal report

Serverlessconf 2016 – New York City: a personal report – is a fascinating read.  Let me get you hooked:

This event left me with the impression (or the confirmation) that there are two paces and speeds at which people are moving.

There is the so called “legacy” pace. This is often characterized by the notion of VMs and virtualization. This market is typically on-prem, owned by VMware and where the majority of workloads (as of today) are running. Very steady.

The second “industry block” is the “new stuff” and this is a truly moving target. #Serverless is yet another model that we are seeing emerging in the last few years. We have moved from Cloud (i.e. IaaS) to opinionated PaaS, to un-opinionated PaaS, to DIY Containers, to CaaS (Containers as a Service) to now #Serverless. There is no way this is going to be the end of it as it’s a frenetic moving target and in every iteration more and more people will be left behind.

This time around was all about the DevOps people being “industry dinosaurs”. So if you are a DevOps persona, know you are legacy already.

Sometimes I feel like I am leaving on a different planet.  All these people are so close, yet so far away …

Packer – a tool for creating VM and container images

With the recent explosion in the virtualization and container technologies, one is often left disoriented.  Questions like “should I use virtual machines or containers?”, “which technology should I use”, and “can I migrate from one to another later?” are just some of those that will need answering.

Here is an open source tool that helps to avoid a few of those questions – Packer (by HashiCorp):

Packer is a tool for creating machine and container images for multiple platforms from a single source configuration.

Have a look at the supported platforms:

  • Amazon EC2 (AMI). Both EBS-backed and instance-store AMIs within EC2, optionally distributed to multiple regions.
  • DigitalOcean. Snapshots for DigitalOcean that can be used to start a pre-configured DigitalOcean instance of any size.
  • Docker. Snapshots for Docker that can be used to start a pre-configured Docker instance.
  • Google Compute Engine. Snapshots for Google Compute Engine that can be used to start a pre-configured Google Compute Engine instance.
  • OpenStack. Images for OpenStack that can be used to start pre-configured OpenStack servers.
  • Parallels (PVM). Exported virtual machines for Parallels, including virtual machine metadata such as RAM, CPUs, etc. These virtual machines are portable and can be started on any platform Parallels runs on.
  • QEMU. Images for KVM or Xen that can be used to start pre-configured KVM or Xen instances.
  • VirtualBox (OVF). Exported virtual machines for VirtualBox, including virtual machine metadata such as RAM, CPUs, etc. These virtual machines are portable and can be started on any platform VirtualBox runs on.
  • VMware (VMX). Exported virtual machines for VMware that can be run within any desktop products such as Fusion, Player, or Workstation, as well as server products such as vSphere.

The only question remaining now, it seems, is “why wouldn’t you use it?”. :)