Some notes on using digiKam as a photo manager

Posted on Wed 08 March 2017 in misc • 1 min read

First of all, this is a very complex and powerful software. I was using shotwell to manage my photos over quite a long period, but it's capabilities are limited. Wherever you go, digiKam is recommended instead.

And well, this is true. The best things in digiKam so far are hierarchical …


Continue reading

Automatically adding a transparent background with ImageMagick

Posted on Wed 18 January 2017 in misc • 1 min read

Yesterday I had to convert some JPEG images with a white background into a PNG with a transparent background. While it is possible to do this by just replacing white with transparent, this also replaces white in other parts of the image where this is not intended. So the better …


Continue reading

Download files with some Python code

Posted on Wed 18 January 2017 in python • 1 min read

If you want to save some files accessible over HTTP(S) to your computer and have to generate their paths with more than bash, saving with Python can be done as following

# With python3
from urllib.request import urlretrieve
urlretrieve(url, local_filename)

Continue reading

Save your Pelican posts as a draft

Posted on Wed 18 January 2017 in misc • 1 min read

Just as a reminder: Adding status: draft to the header of a pelican source written in Markdown sets the draft mode.

(From the pelican docs)


Continue reading

Commonly needed OpenSSL commands

Posted on Fri 06 January 2017 in linux • 1 min read

Very handy list of needed commands: https://www.sslshopper.com/article-most-common-openssl-commands.html

This is especially useful if you hve to check details of a certificate, but also to check which certificate is serverd on non HHTP protocols.


Continue reading

How to test a mail server from the command line

Posted on Fri 06 January 2017 in linux • 1 min read

As I am currently setting up a new mail server, I had to test the new server manually (As of now, the DNS records are not changed, so mail clients are problematic).

If you want to test plain text ports like standard postfix, go simply with telnet localhost 25. If …


Continue reading

Migrate a VM from VirtualBox to libvirt

Posted on Mon 02 January 2017 in linux • 1 min read

Assuming you are using KVM as the libvirt backend:

  1. Find location of harddrive in filesystem
  2. Release and remove harddrive from VirtualBox (has not worked without this step)
  3. Convert to raw image with VBoxManage clonehd --format RAW vboximage.vdi rawimage.raw
  4. Convert to qcow2 image with qemu-img convert -f raw rawimage …

Continue reading

A new beginning

Posted on Mon 02 January 2017 in misc • 1 min read

It has been a while since the last time I published something on this page. So I made some changes, from german to english, new layout and more as a notebook than a blog. We will see if this blog survives this time.


Continue reading

Debugging with IPython shell

Posted on Mon 02 January 2017 in python • 1 min read

Debugging in Python is very easy with IPython, you don't need pdb or so, just do a simple

from IPython import embed

#Inside some functions
embed()

That's all.

Reference

See https://ipython.org/ipython-doc/3/api/generated/IPython.terminal.embed.html#IPython.terminal.embed.embed


Continue reading

Munin plugin für Vodafone LTE Datenverbrauch

Posted on Fri 23 August 2013 in misc • 1 min read

Wir haben bei uns zuhause seit geraumer Zeit einen Internetzugang über LTE von Vodafone. Zum einen sei gesagt, dass dieser Zugang der bislang stabilste ist, den wir hatten. Auch die Geschwindigkeit ist sehr gut. Was jedoch fehlt, ist eine Übersicht über den Datenverbrauch direkt im Router. Auch kann der Router …


Continue reading