Base64 encode on shell

Sometimes you need to encode a string  with a base64 encoding. For example when trying to send a HTTP request with a Basic Authentication header like that: ### own controller: POST Content-Type: application/json Authorization: Basic c25zOlVzZVRoZWZvcmNlCg== { “uuid”: “08e9a8d3-9279-4af5-88ff-ebe42359f0e0”, “eventname”: “”, “data”: { “sitemap_id”: “1234”, “locale”: “de_DE”, “path”: “unigue/page/path”, “title”: “Testpage over API”, “meta_title”: […]

Mount ssh filesystems under Linux or how I mounted my webspace into my root server

Today I had to mount a ssh filesystem under Linux. The reason was, that I had the perception that I would be a very cool idea, to use my old webspace package from, that I only kept because of the 10 included domains, as a backup storage for my root server.The plan was to […]

Setup monit behind Apache proxy under ISPConfig

Today I wanted to setup monit behind Apache proxy on my webserver, which runs ISPConfig ( under Debian. Monit is a OpenSource monitoring tool for Linux (see Requirements I had the following requirements on the solution: monit should only be accessible from the server itself (localhost) monit should run under a special SSL-secured URL (not IP:PORT as […]

Export or extract a certificate to or from PFX

Sometimes you have to deliver or you even get your server certificate files in the pfx file format (personal information exchange, see, that is commonly used in Windows based environments. The following paragraphs show, how to export or extract a certificate to or from PFX. Export cert to PFX In order to export the Certificate, Private Key and any […]

Get your public IP via shell

To get your public IP you can use websites like or just google for it ( But you can also get your public IP via the following Linux shell  command (the smart way :-D): $> curl This gives you an output like that: ip_addr: remote_host: user_agent: curl/7.35.0 port: 47745 lang: connection: keep_alive: encoding: […]

Run a DynDNS client under Raspbian

For a home automation project I have to setup a local DynDNS client on my Banana Pi running with Raspian. Here are the steps I’ve taken to run a DynDNS client under Raspbian (will work on other Debian based Linux distributions too): Install ddclient package: $>sudo apt-get install ddclient This command installs the package and starts the DynDNS […]

Resolve problems with authorized_keys permissions

Sometimes I had problems to connect to a server via public key authentication. In most cases I could solve them by setting up the right permissions for the file and path of the authorized_keys file. This can be done as shown below: $> chmod 700 $HOME/.ssh $> chmod 600 $HOME/.ssh/authorized_keys $> chmod go-w $HOME $HOME/.ssh […]

“Could not resolve host” error

If you get this error message when trying to update the system (see example below) or just pinging an external host … $> sudo pacman -Syu :: Synchronizing package databases… error: failed retrieving file ‘core.db’ from : Could not resolve host: error: failed to update core (download library error) error: failed retrieving file ‘extra.db’ […]

Setup an static IP on Arch Linux

Setup an static IP on Arch Linux can be done by placing a config file in /etc/netctl/: $> sudo nano eth0-Valhalla As you can see, you have to install sudo first. Otherwise you have to switch to root user (su). In the file you have to place the following lines for example: Description=’Valhalla at home eth0′ […]