Visualization of package dependencies

Documentation takes time – sometimes a lot of time. Here a few examples how to create dependencies pictures with Graphviz via command line. These commands can then be easily transferred to a build-process to save your time.

Mac OS X

CentOS 7

Debian 8

Example graph for mtr on Mac OS X

mtr dependencies

Vagrant – Authentication failure

Depending on the vagrant version and how you build/package boxes, you may know the Authentication failure after command “$ vagrant up“. Here now two simple tips, how to prevent or fix it.

Prevention

If you build on an existing box you should not allow Vagrant to automatically insert a new key pair.

Workaround

If the problem already exists…

On command “$ vagrant halt” Vagrant will automatically insert a new keypair.

Visualisation of Docker and Kubernetes

With Weave Scope you have in seconds a beautiful monitoring, visualisation & management for Docker and Kubernetes via your browser. I show with Docker-Selenium a simple example.

Preconditions

Lets go…

That’s it! Now start your browser and open the URL.

weavescope browser

Real-time log monitoring

You may need to watch different log files on automated test runs. With log.io you can simply monitoring log files via browser! This tutorial shows how easy it is.

Preconditions

Preparation

Create new project with following structure and files.

File contents

Configure your Harvesters…

Configure your log server…

Configure your web server…

Create simple init script…

Usage

Now open your browser with URL http://<ip>:28778

Docker Remote API and CentOS 7

This time again some topics in one tutorial. We touch Vagrant with Shell provision (external script), Docker Remote API and something CentOS 7 configuration.

Preconditions

Preparation

If you already have a CentOS 7 with Docker, you can skip these steps. Create a folder with the following 2 files…

Instructions

Now we edit docker.service file. The path may be different!

Note: Be careful if you use tcp://0.0.0.0:4243 !!!!

Read the manual of jq, the power of curl and jq together is awesome.

SSH-life easier with AppleScript

I love the Mac OS X Terminal and to do SSH with it. With increasing age I forget the many SSH connection variables. But with some AppleScript I help myself. Here now 3 simple examples.

Example 1:

User and target are hardcoded.

Example 2

Dialog for user and only target hardcoded.

Example 3

Dialog for user and list for targets.

After exporting as Executable you can put it on places where you want. Do not forget the appropriate icon!

Apache Jmeter and Docker

Okay, this time we will create a Docker-Jmeter test environment. We create some simple (but tiny) Docker images/containers which can be reused for future test runs. Here we follow the DRY rule. Next, we want to achieve.

Preconditions

  • docker installed and running

Preparation

Dockerfile JAVA

Dockerfile Jmeter

JMX file

Create or copy existing JMX file on folder “/tutorial/jmx” with name “simple.jmx”.

Create Jmeter container

Note: The container was created but not running!

Test execution

:)

dnstwist with docker

What happens when users make a typo in URL input? It can display a fake websites. This similar-looking domains can be used to attack you (Domain Name Permutation). With dnstwist you can find such “evil neighbors”. This tutorial shows how to use in a few seconds dnstwist.

Precondition

  • docker installed and running
  • docker-machine installed (optional)

Instructions