Restrict root ssh access to a single IP under Raspbian / Debian / Ubuntu

Today I configured a new backup solution that required me to restrict root ssh access to a single IP for the root user. I got tis to work by going the following steps (on Raspbian GNU/Linux 9): login via ssh on the maschine to access via root modify the /etc/ssh/sshd_config like that

add the following […]

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:

This command installs the package and starts the DynDNS configuration wizard. Select […]

Get MAC address from file system

On Debian based Linux distributions you can get the MAC address of the respective network adapter from the filesystem like shown below:

As you can see, all adapters have their own folder under  /sys/class/net/ that contains  a address file with the corresponding MAC address. If the system is not booted (offline edit). You can have a look into […]