(before LTS support runs out) I have now dist-upgraded several times, always from (old)stable to stable. Originally written for a Jessie => Stretch upgrade, this text still applies for Buster => Bullseye and likely so on into the future. So just replace "jessie" and "stretch" in this text wit...

Context I'm in the process of finally upgrading my Debian install from oldstable (buster) to stable (bullseye). My DAViCal installation uses PostgreSQL for its database backend. Strangely, I have two versions of PostgreSQL (9.6 and 11) and I purged the older one (without deleting the databases, than...

Since CACert still isn't "Browser Trusted", and I still don't want to use letsencrypt, I decided to give this a try. The company resides inside the European Union and is the cheapest I could find. This was the process to get the certificate for anyone who's interested: Buy a certificate (the cheape...

Premise Create a user that has the sole task to run some daemon that also needs to store files on disk. Starting and stopping daemon, as well as accessing these files, needs to be possible via ssh. Otherwise it should be locked down as far as possible. Let's call the user sandy from now on. There al...

Situation Two virtual servers with command line ssh and sftp access, administered from my local machine. I want to migrate everything from one server to the other, without an additional stop on the local machine. The web site in question is located in a www subfolder of the home folder (sometimes al...

Sometimes I want to get a message from my server, e.g. diagnostic stuff from services (SMART daemon, fail2ban), or if someone tries to contact me on my website, and I want it sent to one of my email addresses which is not maintained on that server. I used to use sSMTP for this, but it seems to stop ...

I noticed that my server's (Debian stable) datetime was way off. Years. Strange, because I was sure I had enabled systemd-timesyncd (but apparently never gave it a second thought after that). Looking at systemctl status systemd-timesyncd I found this cryptic message: ● systemd-timesyncd.service - Ne...

Situation I am using PicoCMS1. It's not installed through the global package management: all its files, content & executables (except PHP itself) are located under a single directory. This is not ideal, but common practice; and it has the advantage that it makes maintenance easier. This article ...