For many reasons I prefere managing my Linux servers over SSH. One main reason is, that I can copy and paste commands on my host system and execute them on the target system. Lately, I run into the problem that Cisco AnyConnect forced to route all traffic trough the VPN. In my case Tunnel All was activated in my VPN profile, provided by my remote location. That prevented the SSH connection to my target virtual machines running localy.
This post describes best practice to install and operate a FritzBox behind a Swisscom Internet-Box Router. The steps of course also apply for any other type of router delivered by the internet service provider. Such a setup might be preferred from persons who enjoy the high flexibility of FritzBox routers. Moreover, two approaches are presented how a landline phone number can be integrated, first by an analog interface and second over VoIP.
For more than a decade, I collected many pages with notes and calculations from my apprenticeship and studies. At the end of each semester, I sorted the handouts with my notes and stuffed them into a file folder. For some lessons from the beginning of my studies, I have only the printed scripts with my handwritten notes. Until today, most of these documents are stored in the attic at home and the important files are behind my desk where I can reach them quickly to look something up.
Over the last few years, backing up my IT infrastructure has become more and more complex. Initially it started with simple backups to USB drives using automated scripts with some rsync commands. Today, my backup strategy follows a sophisticated approach that includes both hot and cold backups, storing data at several locations and at least on two technologies, including HDDs, magnetic tapes (LTO) and cloud storage. One major drawback of my current setup is the lack of ability to back up my virtual machines running on my VMware vSphere Hypervisor infrastructure.
This post describes how an email can be sent automatically from a rsync backup script to inform the user about the backup status. This is helpful to ensure that the backup is executed successfully and that the necessary countermeasures can be taken in case of an error. An error may occur if the storage space for the backup target is too small, not accessible, etc. It seems obvious that for personal use nobody would check the backup log every day.
Due to the COVID-19 pandemic, all students and employees of my university are forced to work from home. This led to a significant increase in VPN traffic and forced the IT department to disconnect all clients every 10 hours. Since I carry out model optimizations with Comsol at home, I need a constant connection to the license server at the university. If the VPN connection is disconnected, Comsol stops working and displays a license error message, which in turn causes my optimization routine to crash.
The easiest way to control a Linux computer remotely is via SSH. However, this approach does not work if the remote computer has a desktop environment and a GUI must be operated from the remote location. Under Windows, the Remote Desktop Protocol (RDP) is often used, but other protocols such as Virtual Network Computing (VNC) also exist. The advantage of RDP over others is that for most operating systems the remote desktop client is already installed like RDP under Windows or Remmina under Ubuntu.
Today I would like to share my experience of initializing a bus signal in Simulink based on a struct from the Matlab workspace. For me, the instructions in the documentation and on the internet were not so clear. I will therefore show an example of how this can be implemented. I use this appraoch for an extended Kalman filter (EKF) and unscented Kalman filter (UKF), where I need to initialize the initial states of the estimation algorithm.
The positioning of smartphones is essential for many applications. Unfortunately, the accuracy of the individual smartphone sensors often does not meet the requirements regarding accuracy. In this article the problem is discussed and solved by combining insividaul sensor values. The aproach is based on the Kalman filter. This filter combines several sensors values into one sensor of higher accuracy than the individual sensor accuracy. The Kalman filter can be realized by different methods.