Here are some Badges of courses I've taken.


You get also PDF certificates which you can print.

RIPE Database Expert Course

What you actually learn: 
How to get Data out of the RIPE DB, how to Register new IPs.
Best practice for registering Networks.

1 - RIPE Database Basics
Let's get started! Learn about the different object types and how they relate to each other.

2 - Registering Contact Information
Create your first RIPE Database objects. Learn how to create a person and role object in the RIPE Database.

3 - Querying the RIPE Database
How can you find information in the RIPE Database? And how can you manage your search results?

4 - Protection Mechanisms
All of your RIPE Database objects must be protected. Learn how to add maintainers to your objects.

5 - Creating Assignments
Learn the concept of hierarchical authorisation and create assignments in the RIPE Database.

6 - ROUTE and ROUTE6 Objects
Learn what route and route6 objects are and how you can create them.

7 - Reverse Delegation
Learn how you can setup reverse DNS delegation in the RIPE Database

Introduction to IPv6 Course

What you actually learn:
How IPv6 works and whats different in v6 Protocols (instead of ARP, RIP, DHCP).
How many IP subnets to assign for different needs (sizes of houses, companies).
How to implement some security features, based on IPv6 Addresses.

1. From IPv4 to IPv6
Let's get started! From IPv4 exhaustion straight into IPv6. Let's see why it is a good idea to start working on your IPv6 network.

2. IPv6 Address Basics
Learn how to write IPv6 addresses correctly and calculate your first IPv6 subnets.

3. IPv6 Transition Mechanisms
What are the most used IPv6 Transition Mechanisms? Go through our list to learn the trends.

4. Deploying IPv6
SLAAC, ND, DHCPv6, DNS...don't let the acronyms fool you. Let's look at the best ways to take advantage of IPv6 characteristics.

5. Get and Register IPv6
Do you need to request your IPv6 allocation? Do you have an IPv6 allocation but you don't know how to register it? This section is made especially for you.

6. IPv6 Assignments and Addressing Plans
Learn IPv6 assignment best practices and get inspired for your addressing plan.

7. IPv6 and Security
Discover the different security aspects you need to consider when you deploy IPv6.

well.. who doesn't like badges 😉

online courses, moocs and video lecture portals

I often use e-learning portals to learn new stuff.
You don't need them exactly, nowadays you could learn everything on youtube, medium, github or free e-books.

However, the good about courses/e-learning portals is, the authors do create more courses, get feedback and get better at teaching stuff. You often get a certificate, which can be motivating seeing your progress.

There are also courses made by universities or colleges. Here you can often buy a qualified certification.
These are usually different: high quality, academic correctness where the information comes from. Since I am used to it.. I love this as well. But they often expect previous knowledge to understand the topics.

And there are learning portal joint-ventures from big companies like microsoft, ibm, ...

I found there is a pile full of learning portals out there.
I wanted to give you a list of some for IT and computer science related topics I use.

Search Portals

But first.. there's a company which created a search portal to find online courses:

There is also a search portal for certificates:

Academic Education Sites

HPI (Hasso Plattner Institut):

High quality business, software, new it technology and it law related (german) courses.

A good thing is.. you can enter the courses even afterwards.. if you don't mind learning for the knowledge not for the certificate. Or qualified certificates which can be credited as ECTS if you are a student.

These are the courses I absolved here:

About Semantic Web Technologies

  • Information Service Engineering (semanticweb2017)
  • Linked Data Engineering (semanticweb2016)


  • Blockchain: Hype oder Innovation? (blockchain2018)
  • IT-Recht für Software-Entwickler


Lots of high quality university courses from MIT, Harvard University, University of California Berkley, RWTH Aachen, Technische Universität München, Hongkong University of Science and Technologie, Kyoto University, Peking University...

on different topics

Architecture, Art & Culture, Biology & Life Sciences, Business & Management, Chemistry, Communication, Computer Science, Data Analysis & Statistics, Design, Economics & Finance, Education & Teacher Training, Electronics, Energy & Earth Sciences, Engineering, Environmental Studies, Ethics, Food & Nutrition, Health & Safety, History, Humanities, Language, Law, Literature, Math, Medicine, Music, Philanthropy, Philosophy & Ethics, Physics, Science, Social Sciences

You can get paid qualified certificates which can be credited as ECTS or just view the courses and maybe upgrade to a verified certificate later. You can also get a Micromasters Degree for certain topics.

Education Sites

Pluralsight -

High quality Software development, IT Ops, Professional Business, Data Professional, IT-Security, Design, Photography courses. Some courses have a clearly knowledge prequirements.

Price is a monthly or annually fee
35 $ / Month or 299 $ annually
or the premium version with certification practice exams for 449 $ annuall

There are some weekly free courses... I recommend you to check it out!

Udemy -

Medium to high quality.. for lots of different interesting topics. Often very good and easy explanation. Lots of trainers.. so every course might be different.
Prices for courses are ~10-12 EUR.. 100 EUR

Coursera -

High quality university like MIT, Princeton, UCS or Google courses
You can take courses, get specializations, professional certificates, master track certificates or even degrees. You often need to know pre-requirements
Price range is from free to 30k (masters degree), depending on what program you choose

Udacity -

high quality courses on computer science, programming, autonomous systems, business and career from the big companies like google, nvidia, kaggle, amazon, ibm, unity
Price is 500-999 $ for a topic related nanodegree

Digital Ocean Tutorials, Thomas-Krenn Wiki

When installing a server or an application onto a server, good Tutorials help progressing fast to get to the point.

The best Tutorials related to Server/-Software installation I know are:

setup and use syslog-ng for remote logging

centralizing syslogs in one place is usefull!
my goal was to set up a central server for remote logging of managed switches
There is a usefull tool: syslog-ng
you install it with

apt-get install syslog-ng

or directly

apt-get install syslog-ng-core

if you use

apt-cache search syslog-ng

you can see what plugins exist, like a SQL version

syslog-ng - Enhanced system logging daemon (metapackage)
lwatch - Simple log colorizer
syslog-ng-core - Enhanced system logging daemon (core)
syslog-ng-dbg - Enhanced system logging daemon (debug symbols)
syslog-ng-dev - Enhanced system logging daemon (development files)
syslog-ng-mod-amqp - Enhanced system logging daemon (AMQP plugin)
syslog-ng-mod-basicfuncs-plus - Enhanced system logging daemon (extra template functions)
syslog-ng-mod-geoip - Enhanced system logging daemon (GeoIP plugin)
syslog-ng-mod-json - Enhanced system logging daemon (JSON plugin)
syslog-ng-mod-mongodb - Enhanced system logging daemon (MongoDB plugin)
syslog-ng-mod-redis - Enhanced system logging daemon (Redis plugin)
syslog-ng-mod-riemann - Enhanced system logging daemon (Riemann destination)
syslog-ng-mod-rss - Enhanced system logging daemon (RSS destination)
syslog-ng-mod-smtp - Enhanced system logging daemon (SMTP plugin)
syslog-ng-mod-sql - Enhanced system logging daemon (SQL plugin)
syslog-ng-mod-stomp - Enhanced system logging daemon (STOMP plugin)
syslog-ng-mod-trigger - Enhanced system logging daemon (trigger source)

using it is quite simple
you need to set it up in the config file.My goal was to get external syslogs from the default syslog Port 514 [See Port List]

Further Information on setting up other ports

 The config file is usually located at:


I added the following lines:
to get the data from the port you want to useuse here your external host ip instead of the

source s_extsyslog { network(ip( port(514) transport("udp")); };

the logfile is defined here

destination d_extsyslog { file("/var/log/extsyslog.log"); };

here is defined what shall happen – s_extlog > d_extlog

log { source(s_extsyslog); destination(d_extsyslog); };