Firefox tab crashes by loading maps.google.com on ubuntu 16.04

On a ubuntu 16.04 system firefox crashes by loading maps.google.com:

 The only way to fix this was going to "about:config":

On this page search for "webgl.disabled" and change the value from false
to true:

After that, maps.google.com loads without any problem...

Docker-Machine: how to create a docker vm on a remote virtualbox server

After doing some first steps with docker, i wanted to test docker-swarm. Because of the limited resources of my notebook, i was looking for a Linux with a minimal footprint. In the context of setting up VMs for docker-swarm i found a log of articles about doing that with the tool docker-machine.
It sounds like this tool can create VMs just with one command. (here the documentation).

So let's give it a try:
(You (more...)

Talking about Microservices: A journey to Docker / Snap / CoreOS / Unbuntu Core / Docker-Swarm

A few months ago (13th august 2017) i started my personal journey into this new hype called microservices:

I thought the best way for me to get in touch was to begin with CoreOS. Within 2 weeks i got some first impressions:

Ubuntu 17.10: s2disk/hibernate broken with kernel 4.13.0-32

Last week my notebook refused to startup after s2disk/hibernate. The resume process started up to 100% and then the screen went black and everything stopped...

Hmm...
First idea: Something disappeared inside the grub configuration.

But this was okay.

After nearly one hour my last try was booting an old kernel. And with
schroff@zerberus:/boot$ uname -a
Linux zerberus 4.13.0-17-generic #20-Ubuntu SMP Mon Nov 6 10:04:08 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
s2disk and resume worked again...


Bash: How to trim/truncate variables / get substrings

In a comment to one of the most useless commands postings was shown how to use the rev command to get the last component of  the path out of a log file:
cat log | grep pattern | rev | cut -d '/' -f 1 | rev
If you only have one variable filled with a path, you can get the last component very easy:
schroff@zerberus:~$ myvar=/ab/cd/ef/gh

schroff@zerberus:~$ echo ${myvar##*\/}
gh
?

## removes the longest (more...)

Java 9: JDK without subfolder JRE

In older JDK releases the directory structure was:
bin
db
include
jre
lib
With JEP 220 the jre folder was removed.


A JDK image no longer contains a jre subdirectory, as noted above. Existing code that assumes the existence of that directory might not work correctly.
But this does not mean that there is no JRE any more. You can still download the JRE. There are some minor changes to the JRE like:
The bin (more...)

Oracle SOA Suite 12c: Configuring the SOA Suite Weblogic Server

After
 i had to run the
./config.sh
inside the home/oracle/Oracle/Middleware/Oracle_Home/oracle_common/common/bin

















And then after a
./startWeblogic.sh
inside /bin in the directory, which was configured in the first screenshot of the config.sh, i can open the console:


Oracle SOA Suite: Installing the Fusion Middleware SOA Suite

After the installation of the Fusion Middleware Infrastructur the next step is to install the SOA Suite software.

The software can be found here:



The first try failed with this error:

java -d64 -jar fmw_12.2.1.3.0_soa_quickstart.jar
Launcher-Logdatei ist /tmp/OraInstall2017-10-07_11-47-20PM/launcher2017-10-07_11-47-20PM.log.
Nicht genügend freier Speicherplatz in /tmp/orcl3797124329273264119.tmp, um das Installationsprogramm zu extrahieren. Aktuell 2796 MB. Erforderlich 3532 MB.
Ok. Some cleanups inside /tmp and then:









Next step: Run the config.sh to create a SOA Suite Server....

Docker-CE: How to modify containers with overlays / How to add directories to a standard docker image

After some experiments with docker i wanted to run a tomcat with my own configuration (e.g. memory settings, ports, ...).


The first guess is: Download tomcat, configure everything and then build an image.
BUT: After i learned how to use the -v (--volume) flag for adding some file via the docker command to an image i was wondering, wether creating a new image with only the additional files on top of standard (more...)

Ubuntu Intel Spectre/Meltdown update

One week after the rumors about Spectre and Meltdown (s. Project Zero Blog) my Ubuntu 17.10 got the Intel microcode patch:


root@zerberus:~# apt-get upgrade
Paketlisten werden gelesen... Fertig
Abhängigkeitsbaum wird aufgebaut.      
Statusinformationen werden eingelesen.... Fertig
Paketaktualisierung (Upgrade) wird berechnet... Fertig
Die folgenden Pakete wurden automatisch installiert und werden nicht mehr benötigt:
  linux-headers-4.13.0-17 linux-headers-4.13.0-17-generic
  linux-image-4.13.0-17-generic linux-image-extra-4.13.0-17-generic
Verwenden Sie »apt autoremove«, um sie zu (more...)

Oracle SOA Suite: Installating the Fusion Middleware Infrastructure

After setting up the database (installation, instance setup) and the SOA Suite repository (via rcu) the next step is to install the Oracle Weblogic Infrastructure.

The software can be downloaded here:

(You have to choose "Fusion Middleware Infrastructure Installer)

The unzip the downloaded zip:
 fmw_12.2.1.3.0_infrastructure_Disk1_1of1.zip
and run it: 
java -d64 -jar fmw_12.2.1.3.0_infrastructure.jar
Because the Oracle documentation does not contain pictures of the installer, here the screenshots:










Next step is to run the config.sh to configure the Application server domain.

Review at amazon: Kubernetes: Up & Running

Between christmas and new year i read

The authors state:
"This practical guide shows you how Kubernetes and container technology can help you achieve new levels of velocity, agility, reliability, and efficiency."
I think, yes - this is a practial guide, but within only 166 pages it is far too short to give relevant insights into Kubernetes. There are many commands and YAMLs shown, but the book misses a didactic preparation. Some chapters can (more...)

Docker-Swarm: How to run a mysql database…

After several tests with docker swarm (setting up a swarm, running with more than on master, running a webserver in a swarm) i am thinking about running a mysql database in a swarm.

If you are running a mysql database on one docker host, you have to set up a docker volume, because otherwise data inside the container is gone, if you restart your database container. You can follow this tutorial (more...)

Docker-Swarm: Running with more than one manager-node / How to add a secondary manager or multiple managers

Adding additional masters to a docker swarm is very easy. I just followed the documentation:

On the manager i ran the following command:
alpine:~# docker swarm join-token manager
To add a manager to this swarm, run the following command:

    docker swarm join --token SWMTKN-1-3b7f69d3wgty0u68oab8724z07fkyvgc0w8j37ng1l7jsmbghl-5nrni6ksqnkljvqpp59m5gfh1 192.168.178.46:2377
And on the node:
node03:~# docker swarm join --token SWMTKN-1-3b7f69d3wgty0u68oab8724z07fkyvgc0w8j37ng1
l7jsmbghl-5nrni6ksqnkljvqpp59m5gfh1 192.168.178.46:2377

This node joined a swarm as a manager.
The new (more...)

Docker-CE: Setting up a tomcat in less than a minute and running your JSP…

Last time i wrote about processes and files of a docker container hosting the docker example myapp.py.
Next step was to run a tomcat with a small application inside.

This can be done with theses commands:
  1. Get tomcat from the docker library:
    # docker pull tomcat
    Using default tag: latest
    latest: Pulling from library/tomcat
    3e17c6eae66c: Pull complete
    fdfb54153de7: Pull complete
    a4ca6e73242a: Pull complete
    5161d2a139e2: Pull complete
    7659b327f9ec: Pull complete
    ce47e69f11ad: Pull complete
    7d946df3a3d8: Pull (more...)

Docker-Swarm: Running a minimal webserver in a swarm

In my last posting to docker swarm i created a swarm on virtualbox with alpine linux with a hdd footprint of 290MB per node:
There are some tutorials out there with running a nginx or a java webserver in a container but >100MB for each node seems far to much for my tests.

So i decided to create a application which listens on port 8080 with netcat. I created a directory ncweb with ncweb.sh:
(more...)

Docker-Swarm: One manager, two nodes with Alpine Linux

After creating a Alpine Linux VM inside virtualbox and after adding docker because of the small disk footprint (Alpine Linux: 170MB | with docker: 280MB) i performed the following steps to create a docker swarm:
  • cloning the vm twice
  • assigning a static ip to the manager node
  • create new MACs for the network interface cards on the nodes 


Then i followed the tutorial https://docs.docker.com/engine/swarm/swarm-tutorial/create-swarm/ but without running the docker-machine commands, because i have (more...)

OpenJDK 9: Limitations/shortcomings of the Jshell

Jshell is a quite powerful tool to do some quick explorations and to write some scripts.

If found the following limitations:
  • No syntax highlighting
  • Only comments with // are allowed
    if you open a script file with
     /**
      *  My comments
      */
    this will work only many warnings.
    |  Error:
    |  illegal start of expression
    |   * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
    |   ^
    |  Error:
    (more...)

Docker-CE: Creating a small Linux as base OS for running a Docker cluster

After some first steps with docker i wanted to run more than one docker node. The problem is, that i have very limited resources on my laptop.
  • CoreOS (see here)
    consumes about 600MB diskspace
  • UbuntuCore (see here)
    consumes about 1.9GB diskspace
To setup CoreOS you have to learn ignition - otherwise every change is lost after a reboot. For UbuntuCore you have to use an UbuntuOne account to get it running.

I (more...)

Docker-CE: Get Started Tutorial – processes / files / HTTP headers

Inside my docker installation on ubuntu server i performed the official docker tutorial part 2: "containers"

Ok. Not really interesting, because the tutorial describes all steps very well (except the point, that you have to install python3-pip and you have to run pip3 and not pip).

Here the interesting part:

After i started the container ("docker run -p 4000:80 friendlyhello") i got the following:
root@ubuntuserver:/var/lib/docker/image# docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                  (more...)